From 90897f570ed5777539dd7dda533ae18e68edc31c Mon Sep 17 00:00:00 2001 From: "Steven J. Plimpton" Date: Tue, 31 Jul 2018 15:27:09 -0600 Subject: [PATCH] changes for Intro and Howto doc pages --- doc/src/Errors.txt | 2 +- doc/src/Examples.txt | 6 +- doc/src/Howto.txt | 128 + doc/src/Howto_2d.txt | 48 + doc/src/Howto_barostat.txt | 75 + ...ial_bash_on_windows.txt => Howto_bash.txt} | 1 + doc/src/Howto_bioFF.txt | 101 + doc/src/Howto_body.txt | 456 +++ doc/src/Howto_chunk.txt | 166 + doc/src/Howto_coreshell.txt | 253 ++ doc/src/Howto_couple.txt | 105 + doc/src/Howto_diffusion.txt | 31 + doc/src/Howto_dispersion.txt | 108 + doc/src/Howto_drude.txt | 77 + .../{tutorial_drude.txt => Howto_drude2.txt} | 0 doc/src/Howto_elastic.txt | 47 + .../{tutorial_github.txt => Howto_github.txt} | 10 +- doc/src/Howto_granular.txt | 57 + doc/src/Howto_kappa.txt | 90 + doc/src/Howto_library.txt | 208 ++ doc/src/Howto_manifold.txt | 41 + doc/src/Howto_multiple.txt | 95 + doc/src/Howto_nemd.txt | 48 + doc/src/Howto_output.txt | 307 ++ doc/src/Howto_polarizable.txt | 81 + ...torial_pylammps.txt => Howto_pylammps.txt} | 21 +- doc/src/Howto_replica.txt | 61 + doc/src/Howto_restart.txt | 97 + doc/src/Howto_spc.txt | 54 + doc/src/Howto_spherical.txt | 243 ++ doc/src/Howto_spins.txt | 59 + doc/src/Howto_temperature.txt | 40 + doc/src/Howto_thermostat.txt | 89 + doc/src/Howto_tip3p.txt | 69 + doc/src/Howto_tip4p.txt | 112 + doc/src/Howto_triclinic.txt | 213 ++ doc/src/Howto_viscosity.txt | 133 + doc/src/Howto_viz.txt | 40 + doc/src/Howto_walls.txt | 80 + doc/src/Intro.txt | 43 + doc/src/Manual.txt | 173 +- doc/src/Manual_version.txt | 33 + doc/src/Modify_body.txt | 7 +- doc/src/Modify_contribute.txt | 21 +- doc/src/Packages_details.txt | 58 +- doc/src/Packages_standard.txt | 12 +- doc/src/Packages_user.txt | 2 +- doc/src/Python_library.txt | 14 +- doc/src/Python_pylammps.txt | 4 +- doc/src/Section_history.txt | 135 - doc/src/Section_howto.txt | 3011 ----------------- doc/src/Section_intro.txt | 550 --- doc/src/Section_start.txt | 52 +- doc/src/Speed.txt | 2 +- doc/src/Tools.txt | 6 +- doc/src/angle_cosine_periodic.txt | 8 +- doc/src/atom_style.txt | 21 +- doc/src/body.txt | 4 +- doc/src/boundary.txt | 6 +- doc/src/box.txt | 6 +- doc/src/change_box.txt | 18 +- doc/src/compute.txt | 2 +- doc/src/compute_ackland_atom.txt | 2 +- doc/src/compute_angle.txt | 4 +- doc/src/compute_angle_local.txt | 4 +- doc/src/compute_angmom_chunk.txt | 11 +- doc/src/compute_basal_atom.txt | 5 +- doc/src/compute_body_local.txt | 15 +- doc/src/compute_bond.txt | 4 +- doc/src/compute_bond_local.txt | 4 +- doc/src/compute_centro_atom.txt | 4 +- doc/src/compute_chunk_atom.txt | 25 +- doc/src/compute_cluster_atom.txt | 2 +- doc/src/compute_cna_atom.txt | 2 +- doc/src/compute_cnp_atom.txt | 2 +- doc/src/compute_com.txt | 5 +- doc/src/compute_com_chunk.txt | 12 +- doc/src/compute_contact_atom.txt | 2 +- doc/src/compute_coord_atom.txt | 5 +- doc/src/compute_damage_atom.txt | 2 +- doc/src/compute_dihedral.txt | 4 +- doc/src/compute_dihedral_local.txt | 4 +- doc/src/compute_dilatation_atom.txt | 5 +- doc/src/compute_dipole_chunk.txt | 11 +- doc/src/compute_displace_atom.txt | 5 +- doc/src/compute_dpd.txt | 6 +- doc/src/compute_dpd_atom.txt | 6 +- doc/src/compute_edpd_temp_atom.txt | 6 +- doc/src/compute_entropy_atom.txt | 4 +- doc/src/compute_erotate_asphere.txt | 2 +- doc/src/compute_erotate_rigid.txt | 6 +- doc/src/compute_erotate_sphere.txt | 2 +- doc/src/compute_erotate_sphere_atom.txt | 2 +- doc/src/compute_event_displace.txt | 2 +- doc/src/compute_fep.txt | 4 +- doc/src/compute_global_atom.txt | 4 +- doc/src/compute_group_group.txt | 4 +- doc/src/compute_gyration.txt | 4 +- doc/src/compute_gyration_chunk.txt | 11 +- doc/src/compute_heat_flux.txt | 10 +- doc/src/compute_hexorder_atom.txt | 7 +- doc/src/compute_improper.txt | 4 +- doc/src/compute_improper_local.txt | 4 +- doc/src/compute_inertia_chunk.txt | 11 +- doc/src/compute_ke.txt | 2 +- doc/src/compute_ke_atom.txt | 2 +- doc/src/compute_ke_atom_eff.txt | 6 +- doc/src/compute_ke_eff.txt | 2 +- doc/src/compute_ke_rigid.txt | 4 +- doc/src/compute_meso_e_atom.txt | 2 +- doc/src/compute_meso_rho_atom.txt | 2 +- doc/src/compute_meso_t_atom.txt | 2 +- doc/src/compute_msd.txt | 5 +- doc/src/compute_msd_chunk.txt | 9 +- doc/src/compute_msd_nongauss.txt | 5 +- doc/src/compute_omega_chunk.txt | 11 +- doc/src/compute_orientorder_atom.txt | 7 +- doc/src/compute_pair.txt | 5 +- doc/src/compute_pair_local.txt | 4 +- doc/src/compute_pe.txt | 5 +- doc/src/compute_pe_atom.txt | 2 +- doc/src/compute_plasticity_atom.txt | 5 +- doc/src/compute_pressure.txt | 4 +- doc/src/compute_property_atom.txt | 14 +- doc/src/compute_property_chunk.txt | 15 +- doc/src/compute_property_local.txt | 12 +- doc/src/compute_rdf.txt | 2 +- doc/src/compute_reduce.txt | 2 +- doc/src/compute_rigid_local.txt | 10 +- doc/src/compute_saed.txt | 7 +- doc/src/compute_slice.txt | 4 +- doc/src/compute_smd_contact_radius.txt | 6 +- doc/src/compute_smd_damage.txt | 8 +- doc/src/compute_smd_hourglass_error.txt | 8 +- doc/src/compute_smd_internal_energy.txt | 4 +- doc/src/compute_smd_plastic_strain.txt | 4 +- doc/src/compute_smd_plastic_strain_rate.txt | 4 +- doc/src/compute_smd_rho.txt | 4 +- doc/src/compute_smd_tlsph_defgrad.txt | 5 +- doc/src/compute_smd_tlsph_dt.txt | 4 +- doc/src/compute_smd_tlsph_num_neighs.txt | 4 +- doc/src/compute_smd_tlsph_shape.txt | 5 +- doc/src/compute_smd_tlsph_strain.txt | 5 +- doc/src/compute_smd_tlsph_strain_rate.txt | 5 +- doc/src/compute_smd_tlsph_stress.txt | 9 +- .../compute_smd_triangle_mesh_vertices.txt | 6 +- doc/src/compute_smd_ulsph_num_neighs.txt | 2 +- doc/src/compute_smd_ulsph_strain.txt | 2 +- doc/src/compute_smd_ulsph_strain_rate.txt | 5 +- doc/src/compute_smd_ulsph_stress.txt | 5 +- doc/src/compute_smd_vol.txt | 4 +- doc/src/compute_sna_atom.txt | 5 +- doc/src/compute_stress_atom.txt | 5 +- doc/src/compute_tdpd_cc_atom.txt | 6 +- doc/src/compute_temp.txt | 8 +- doc/src/compute_temp_asphere.txt | 8 +- doc/src/compute_temp_body.txt | 8 +- doc/src/compute_temp_chunk.txt | 16 +- doc/src/compute_temp_com.txt | 8 +- doc/src/compute_temp_cs.txt | 11 +- doc/src/compute_temp_deform.txt | 8 +- doc/src/compute_temp_deform_eff.txt | 4 +- doc/src/compute_temp_drude.txt | 12 +- doc/src/compute_temp_eff.txt | 4 +- doc/src/compute_temp_partial.txt | 8 +- doc/src/compute_temp_profile.txt | 8 +- doc/src/compute_temp_ramp.txt | 8 +- doc/src/compute_temp_region.txt | 8 +- doc/src/compute_temp_region_eff.txt | 4 +- doc/src/compute_temp_rotate.txt | 8 +- doc/src/compute_temp_sphere.txt | 8 +- doc/src/compute_ti.txt | 5 +- doc/src/compute_torque_chunk.txt | 9 +- doc/src/compute_vacf.txt | 5 +- doc/src/compute_vcm_chunk.txt | 11 +- doc/src/compute_voronoi_atom.txt | 26 +- doc/src/compute_xrd.txt | 2 +- doc/src/create_box.txt | 6 +- doc/src/dimension.txt | 2 +- doc/src/dump.txt | 14 +- doc/src/dump_image.txt | 14 +- doc/src/fix.txt | 2 +- doc/src/fix_adapt.txt | 8 +- doc/src/fix_adapt_fep.txt | 8 +- doc/src/fix_addforce.txt | 10 +- doc/src/fix_addtorque.txt | 10 +- doc/src/fix_append_atoms.txt | 8 +- doc/src/fix_atc.txt | 8 +- doc/src/fix_atom_swap.txt | 4 +- doc/src/fix_ave_atom.txt | 14 +- doc/src/fix_ave_chunk.txt | 33 +- doc/src/fix_ave_correlate.txt | 21 +- doc/src/fix_ave_histo.txt | 15 +- doc/src/fix_ave_time.txt | 9 +- doc/src/fix_aveforce.txt | 8 +- doc/src/fix_balance.txt | 4 +- doc/src/fix_bond_break.txt | 4 +- doc/src/fix_bond_create.txt | 4 +- doc/src/fix_bond_react.txt | 5 +- doc/src/fix_bond_swap.txt | 14 +- doc/src/fix_box_relax.txt | 20 +- doc/src/fix_cmap.txt | 6 +- doc/src/fix_colvars.txt | 6 +- doc/src/fix_controller.txt | 6 +- doc/src/fix_deform.txt | 7 +- doc/src/fix_deposit.txt | 10 +- doc/src/fix_dpd_source.txt | 8 +- doc/src/fix_drag.txt | 6 +- doc/src/fix_drude.txt | 8 +- doc/src/fix_drude_transform.txt | 4 +- doc/src/fix_dt_reset.txt | 4 +- doc/src/fix_efield.txt | 9 +- doc/src/fix_enforce2d.txt | 6 +- doc/src/fix_evaporate.txt | 6 +- doc/src/fix_external.txt | 13 +- doc/src/fix_filter_corotate.txt | 7 +- doc/src/fix_flow_gauss.txt | 10 +- doc/src/fix_freeze.txt | 8 +- doc/src/fix_gcmc.txt | 4 +- doc/src/fix_gld.txt | 2 +- doc/src/fix_gle.txt | 6 +- doc/src/fix_gravity.txt | 10 +- doc/src/fix_halt.txt | 8 +- doc/src/fix_heat.txt | 11 +- doc/src/fix_imd.txt | 6 +- doc/src/fix_indent.txt | 4 +- doc/src/fix_langevin.txt | 10 +- doc/src/fix_langevin_drude.txt | 9 +- doc/src/fix_langevin_eff.txt | 8 +- doc/src/fix_latte.txt | 6 +- doc/src/fix_lb_fluid.txt | 6 +- doc/src/fix_lb_momentum.txt | 8 +- doc/src/fix_lb_pc.txt | 8 +- doc/src/fix_lb_rigid_pc_sphere.txt | 34 +- doc/src/fix_lb_viscous.txt | 6 +- doc/src/fix_lineforce.txt | 6 +- doc/src/fix_manifoldforce.txt | 8 +- doc/src/fix_meso.txt | 8 +- doc/src/fix_meso_stationary.txt | 8 +- doc/src/fix_momentum.txt | 8 +- doc/src/fix_move.txt | 7 +- doc/src/fix_msst.txt | 4 +- doc/src/fix_mvv_dpd.txt | 8 +- doc/src/fix_neb.txt | 12 +- doc/src/fix_nh.txt | 13 +- doc/src/fix_nphug.txt | 6 +- doc/src/fix_nve.txt | 8 +- doc/src/fix_nve_asphere.txt | 8 +- doc/src/fix_nve_asphere_noforce.txt | 8 +- doc/src/fix_nve_body.txt | 14 +- doc/src/fix_nve_eff.txt | 8 +- doc/src/fix_nve_limit.txt | 16 +- doc/src/fix_nve_line.txt | 14 +- doc/src/fix_nve_manifold_rattle.txt | 10 +- doc/src/fix_nve_noforce.txt | 8 +- doc/src/fix_nve_sphere.txt | 8 +- doc/src/fix_nve_tri.txt | 16 +- doc/src/fix_nvk.txt | 8 +- doc/src/fix_nvt_manifold_rattle.txt | 18 +- doc/src/fix_oneway.txt | 8 +- doc/src/fix_orient.txt | 12 +- doc/src/fix_phonon.txt | 2 +- doc/src/fix_pimd.txt | 15 +- doc/src/fix_planeforce.txt | 6 +- doc/src/fix_poems.txt | 6 +- doc/src/fix_pour.txt | 6 +- doc/src/fix_precession_spin.txt | 4 +- doc/src/fix_press_berendsen.txt | 7 +- doc/src/fix_print.txt | 8 +- doc/src/fix_property_atom.txt | 27 +- doc/src/fix_python_move.txt | 8 +- doc/src/fix_qbmsst.txt | 8 +- doc/src/fix_qeq.txt | 5 +- doc/src/fix_qeq_comb.txt | 6 +- doc/src/fix_qeq_reax.txt | 4 +- doc/src/fix_qmmm.txt | 6 +- doc/src/fix_reax_bonds.txt | 8 +- doc/src/fix_reaxc_species.txt | 4 +- doc/src/fix_recenter.txt | 10 +- doc/src/fix_restrain.txt | 4 +- doc/src/fix_rigid.txt | 36 +- doc/src/fix_setforce.txt | 8 +- doc/src/fix_shake.txt | 7 +- doc/src/fix_smd.txt | 12 +- doc/src/fix_smd_setvel.txt | 6 +- doc/src/fix_spring.txt | 22 +- doc/src/fix_spring_chunk.txt | 4 +- doc/src/fix_spring_rg.txt | 8 +- doc/src/fix_spring_self.txt | 8 +- doc/src/fix_srd.txt | 10 +- doc/src/fix_store_force.txt | 8 +- doc/src/fix_store_state.txt | 8 +- doc/src/fix_temp_berendsen.txt | 10 +- doc/src/fix_temp_csvr.txt | 10 +- doc/src/fix_temp_rescale.txt | 10 +- doc/src/fix_temp_rescale_eff.txt | 6 +- doc/src/fix_thermal_conductivity.txt | 6 +- doc/src/fix_ti_spring.txt | 13 +- doc/src/fix_tmd.txt | 3 +- doc/src/fix_ttm.txt | 23 +- doc/src/fix_vector.txt | 7 +- doc/src/fix_viscosity.txt | 27 +- doc/src/fix_viscous.txt | 6 +- doc/src/fix_wall.txt | 16 +- doc/src/fix_wall_body_polygon.txt | 10 +- doc/src/fix_wall_body_polyhedron.txt | 10 +- doc/src/fix_wall_gran.txt | 6 +- doc/src/fix_wall_gran_region.txt | 6 +- doc/src/fix_wall_piston.txt | 8 +- doc/src/fix_wall_reflect.txt | 8 +- doc/src/fix_wall_region.txt | 11 +- doc/src/fix_wall_srd.txt | 6 +- doc/src/improper_umbrella.txt | 2 +- doc/src/kspace_modify.txt | 18 +- doc/src/kspace_style.txt | 15 +- doc/src/lammps_tutorials.txt | 6 - doc/src/molecule.txt | 5 +- doc/src/neb.txt | 5 +- doc/src/pair_body_nparticle.txt | 11 +- doc/src/pair_body_rounded_polygon.txt | 5 +- doc/src/pair_body_rounded_polyhedron.txt | 5 +- doc/src/pair_born.txt | 8 +- doc/src/pair_buck.txt | 5 +- doc/src/pair_coul.txt | 26 +- doc/src/pair_cs.txt | 4 +- doc/src/pair_hbond_dreiding.txt | 8 +- doc/src/pair_lj.txt | 26 +- doc/src/pair_lj_long.txt | 2 +- doc/src/pair_thole.txt | 4 +- doc/src/prd.txt | 4 +- doc/src/read_data.txt | 12 +- doc/src/region.txt | 6 +- doc/src/run.txt | 6 +- doc/src/tad.txt | 5 +- doc/src/temper.txt | 15 +- doc/src/thermo_style.txt | 10 +- doc/src/tutorials.txt | 15 - doc/src/velocity.txt | 17 +- 338 files changed, 5122 insertions(+), 5113 deletions(-) create mode 100644 doc/src/Howto.txt create mode 100644 doc/src/Howto_2d.txt create mode 100644 doc/src/Howto_barostat.txt rename doc/src/{tutorial_bash_on_windows.txt => Howto_bash.txt} (99%) mode change 100644 => 100755 create mode 100644 doc/src/Howto_bioFF.txt create mode 100644 doc/src/Howto_body.txt create mode 100644 doc/src/Howto_chunk.txt create mode 100644 doc/src/Howto_coreshell.txt create mode 100644 doc/src/Howto_couple.txt create mode 100644 doc/src/Howto_diffusion.txt create mode 100644 doc/src/Howto_dispersion.txt create mode 100644 doc/src/Howto_drude.txt rename doc/src/{tutorial_drude.txt => Howto_drude2.txt} (100%) create mode 100644 doc/src/Howto_elastic.txt rename doc/src/{tutorial_github.txt => Howto_github.txt} (98%) create mode 100644 doc/src/Howto_granular.txt create mode 100644 doc/src/Howto_kappa.txt create mode 100644 doc/src/Howto_library.txt create mode 100644 doc/src/Howto_manifold.txt create mode 100644 doc/src/Howto_multiple.txt create mode 100644 doc/src/Howto_nemd.txt create mode 100644 doc/src/Howto_output.txt create mode 100644 doc/src/Howto_polarizable.txt rename doc/src/{tutorial_pylammps.txt => Howto_pylammps.txt} (95%) create mode 100644 doc/src/Howto_replica.txt create mode 100644 doc/src/Howto_restart.txt create mode 100644 doc/src/Howto_spc.txt create mode 100644 doc/src/Howto_spherical.txt create mode 100644 doc/src/Howto_spins.txt create mode 100644 doc/src/Howto_temperature.txt create mode 100644 doc/src/Howto_thermostat.txt create mode 100644 doc/src/Howto_tip3p.txt create mode 100644 doc/src/Howto_tip4p.txt create mode 100644 doc/src/Howto_triclinic.txt create mode 100644 doc/src/Howto_viscosity.txt create mode 100644 doc/src/Howto_viz.txt create mode 100644 doc/src/Howto_walls.txt create mode 100644 doc/src/Intro.txt create mode 100644 doc/src/Manual_version.txt delete mode 100644 doc/src/Section_history.txt delete mode 100644 doc/src/Section_howto.txt delete mode 100644 doc/src/Section_intro.txt delete mode 100644 doc/src/lammps_tutorials.txt delete mode 100644 doc/src/tutorials.txt diff --git a/doc/src/Errors.txt b/doc/src/Errors.txt index 7bc520c19d..92a577c5f2 100644 --- a/doc/src/Errors.txt +++ b/doc/src/Errors.txt @@ -1,6 +1,6 @@ "Previous Section"_Python.html - "LAMMPS WWW Site"_lws - "LAMMPS Documentation"_ld - "LAMMPS Commands"_lc - "Next -Section"_Section_history.html :c +Section"_Manual.html :c :link(lws,http://lammps.sandia.gov) :link(ld,Manual.html) diff --git a/doc/src/Examples.txt b/doc/src/Examples.txt index 467ddcc959..b01b289d5e 100644 --- a/doc/src/Examples.txt +++ b/doc/src/Examples.txt @@ -1,6 +1,6 @@ -"Previous Section"_Section_howto.html - "LAMMPS WWW Site"_lws - -"LAMMPS Documentation"_ld - "LAMMPS Commands"_lc - "Next -Section"_Section_perf.html :c +"Previous Section"_Howto.html - "LAMMPS WWW Site"_lws - "LAMMPS +Documentation"_ld - "LAMMPS Commands"_lc - "Next +Section"_Tools.html :c :link(lws,http://lammps.sandia.gov) :link(ld,Manual.html) diff --git a/doc/src/Howto.txt b/doc/src/Howto.txt new file mode 100644 index 0000000000..d9a60d1ef4 --- /dev/null +++ b/doc/src/Howto.txt @@ -0,0 +1,128 @@ +"Previous Section"_Performance.html - "LAMMPS WWW Site"_lws - +"LAMMPS Documentation"_ld - "LAMMPS Commands"_lc - "Next +Section"_Examples.html :c + +:link(lws,http://lammps.sandia.gov) +:link(ld,Manual.html) +:link(lc,Commands.html#comm) + +:line + +How to discussions :h2 + +These doc pages describe how to perform various tasks with LAMMPS, +both for users and developers. The +"glossary"_http://lammps.sandia.gov website page also lists MD +terminology with links to corresponding LAMMPS manual pages. + +The example input scripts included in the examples dir of the LAMMPS +distribution and highlighted on the "Examples"_Examples.html doc page +also show how to setup and run various kinds of simulations. + + + + + +"Using GitHub with LAMMPS"_Howto_github.html +"PyLAMMPS interface to LAMMPS"_Howto_pylammps.html +"Using LAMMPS with bash on Windows"_Howto_bash.html + +"Restart a simulation"_Howto_restart.html +"Visualize LAMMPS snapshots"_Howto_viz.html +"Run multiple simulations from one input script"_Howto_multiple.html +"Multi-replica simulations"_Howto_replica.html +"Library interface to LAMMPS"_Howto_library.html +"Couple LAMMPS to other codes"_Howto_couple.html :all(b) + +"Output from LAMMPS (thermo, dumps, computes, fixes, variables)"_Howto_output.html +"Use chunks to calculate system properties"_Howto_chunk.html :all(b) + +"2d simulations"_Howto_2d.html +"Triclinic (non-orthogonal) simulation boxes"_Howto_triclinic.html +"Walls"_Howto_walls.html +"NEMD simulations"_Howto_nemd.html +"Granular models"_Howto_granular.html +"Finite-size spherical and aspherical particles"_Howto_spherical.html +"Long-range dispersion settings"_Howto_dispersion.html :all(b) + +"Calculate temperature"_Howto_temperature.html +"Thermostats"_Howto_thermostat.html +"Barostats"_Howto_barostat.html +"Calculate elastic constants"_Howto_elastic.html +"Calculate thermal conductivity"_Howto_kappa.html +"Calculate viscosity"_Howto_viscosity.html +"Calculate a diffusion coefficient"_Howto_diffusion.html :all(b) + +"CHARMM, AMBER, and DREIDING force fields"_Howto_bioFF.html +"TIP3P water model"_Howto_tip3p.html +"TIP4P water model"_Howto_tip4p.html +"SPC water model"_Howto_spc.html :all(b) + +"Body style particles"_Howto_body.html +"Polarizable models"_Howto_polarizable.html +"Adiabatic core/shell model"_Howto_coreshell.html +"Drude induced dipoles"_Howto_drude.html +"Drude induced dipoles (extended)"_Howto_drude2.html :all(b) +"Manifolds (surfaces)"_Howto_manifold.html +"Magnetic spins"_Howto_spins.html + + diff --git a/doc/src/Howto_2d.txt b/doc/src/Howto_2d.txt new file mode 100644 index 0000000000..ea11a7d546 --- /dev/null +++ b/doc/src/Howto_2d.txt @@ -0,0 +1,48 @@ +"Higher level section"_Howto.html - "LAMMPS WWW Site"_lws - "LAMMPS +Documentation"_ld - "LAMMPS Commands"_lc :c + +:link(lws,http://lammps.sandia.gov) +:link(ld,Manual.html) +:link(lc,Section_commands.html#comm) + +:line + +2d simulations :h3 + +Use the "dimension"_dimension.html command to specify a 2d simulation. + +Make the simulation box periodic in z via the "boundary"_boundary.html +command. This is the default. + +If using the "create box"_create_box.html command to define a +simulation box, set the z dimensions narrow, but finite, so that the +create_atoms command will tile the 3d simulation box with a single z +plane of atoms - e.g. + +"create box"_create_box.html 1 -10 10 -10 10 -0.25 0.25 :pre + +If using the "read data"_read_data.html command to read in a file of +atom coordinates, set the "zlo zhi" values to be finite but narrow, +similar to the create_box command settings just described. For each +atom in the file, assign a z coordinate so it falls inside the +z-boundaries of the box - e.g. 0.0. + +Use the "fix enforce2d"_fix_enforce2d.html command as the last +defined fix to insure that the z-components of velocities and forces +are zeroed out every timestep. The reason to make it the last fix is +so that any forces induced by other fixes will be zeroed out. + +Many of the example input scripts included in the LAMMPS distribution +are for 2d models. + +NOTE: Some models in LAMMPS treat particles as finite-size spheres, as +opposed to point particles. See the "atom_style +sphere"_atom_style.html and "fix nve/sphere"_fix_nve_sphere.html +commands for details. By default, for 2d simulations, such particles +will still be modeled as 3d spheres, not 2d discs (circles), meaning +their moment of inertia will be that of a sphere. If you wish to +model them as 2d discs, see the "set density/disc"_set.html command +and the {disc} option for the "fix nve/sphere"_fix_nve_sphere.html, +"fix nvt/sphere"_fix_nvt_sphere.html, "fix +nph/sphere"_fix_nph_sphere.html, "fix npt/sphere"_fix_npt_sphere.html +commands. diff --git a/doc/src/Howto_barostat.txt b/doc/src/Howto_barostat.txt new file mode 100644 index 0000000000..b289ebfc4c --- /dev/null +++ b/doc/src/Howto_barostat.txt @@ -0,0 +1,75 @@ +"Higher level section"_Howto.html - "LAMMPS WWW Site"_lws - "LAMMPS +Documentation"_ld - "LAMMPS Commands"_lc :c + +:link(lws,http://lammps.sandia.gov) +:link(ld,Manual.html) +:link(lc,Section_commands.html#comm) + +:line + +Barostats :h3 + +Barostatting means controlling the pressure in an MD simulation. +"Thermostatting"_Howto_thermostat.html means controlling the +temperature of the particles. Since the pressure includes a kinetic +component due to particle velocities, both these operations require +calculation of the temperature. Typically a target temperature (T) +and/or pressure (P) is specified by the user, and the thermostat or +barostat attempts to equilibrate the system to the requested T and/or +P. + +Barostatting in LAMMPS is performed by "fixes"_fix.html. Two +barosttating methods are currently available: Nose-Hoover (npt and +nph) and Berendsen: + +"fix npt"_fix_nh.html +"fix npt/sphere"_fix_npt_sphere.html +"fix npt/asphere"_fix_npt_asphere.html +"fix nph"_fix_nh.html +"fix press/berendsen"_fix_press_berendsen.html :ul + +The "fix npt"_fix_nh.html commands include a Nose-Hoover thermostat +and barostat. "Fix nph"_fix_nh.html is just a Nose/Hoover barostat; +it does no thermostatting. Both "fix nph"_fix_nh.html and "fix +press/berendsen"_fix_press_berendsen.html can be used in conjunction +with any of the thermostatting fixes. + +As with the "thermostats"_Howto_thermostat.html, "fix npt"_fix_nh.html +and "fix nph"_fix_nh.html only use translational motion of the +particles in computing T and P and performing thermo/barostatting. +"Fix npt/sphere"_fix_npt_sphere.html and "fix +npt/asphere"_fix_npt_asphere.html thermo/barostat using not only +translation velocities but also rotational velocities for spherical +and aspherical particles. + +All of the barostatting fixes use the "compute +pressure"_compute_pressure.html compute to calculate a current +pressure. By default, this compute is created with a simple "compute +temp"_compute_temp.html (see the last argument of the "compute +pressure"_compute_pressure.html command), which is used to calculated +the kinetic component of the pressure. The barostatting fixes can +also use temperature computes that remove bias for the purpose of +computing the kinetic component which contributes to the current +pressure. See the doc pages for the individual fixes and for the +"fix_modify"_fix_modify.html command for instructions on how to assign +a temperature or pressure compute to a barostatting fix. + +NOTE: As with the thermostats, the Nose/Hoover methods ("fix +npt"_fix_nh.html and "fix nph"_fix_nh.html) perform time integration. +"Fix press/berendsen"_fix_press_berendsen.html does NOT, so it should +be used with one of the constant NVE fixes or with one of the NVT +fixes. + +Thermodynamic output, which can be setup via the +"thermo_style"_thermo_style.html command, often includes pressure +values. As explained on the doc page for the +"thermo_style"_thermo_style.html command, the default pressure is +setup by the thermo command itself. It is NOT the presure associated +with any barostatting fix you have defined or with any compute you +have defined that calculates a presure. The doc pages for the +barostatting fixes explain the ID of the pressure compute they create. +Thus if you want to view these pressurse, you need to specify them +explicitly via the "thermo_style custom"_thermo_style.html command. +Or you can use the "thermo_modify"_thermo_modify.html command to +re-define what pressure compute is used for default thermodynamic +output. diff --git a/doc/src/tutorial_bash_on_windows.txt b/doc/src/Howto_bash.txt old mode 100644 new mode 100755 similarity index 99% rename from doc/src/tutorial_bash_on_windows.txt rename to doc/src/Howto_bash.txt index 66712bdffa..572157ab55 --- a/doc/src/tutorial_bash_on_windows.txt +++ b/doc/src/Howto_bash.txt @@ -10,6 +10,7 @@ Using LAMMPS with Bash on Windows :h3 [written by Richard Berger] :line + Starting with Windows 10 you can install Linux tools directly in Windows. This allows you to compile LAMMPS following the same procedure as on a real Ubuntu Linux installation. Software can be easily installed using the package manager diff --git a/doc/src/Howto_bioFF.txt b/doc/src/Howto_bioFF.txt new file mode 100644 index 0000000000..91d6eb0a8e --- /dev/null +++ b/doc/src/Howto_bioFF.txt @@ -0,0 +1,101 @@ +"Higher level section"_Howto.html - "LAMMPS WWW Site"_lws - "LAMMPS +Documentation"_ld - "LAMMPS Commands"_lc :c + +:link(lws,http://lammps.sandia.gov) +:link(ld,Manual.html) +:link(lc,Section_commands.html#comm) + +:line + +CHARMM, AMBER, and DREIDING force fields :h3 + +A force field has 2 parts: the formulas that define it and the +coefficients used for a particular system. Here we only discuss +formulas implemented in LAMMPS that correspond to formulas commonly +used in the CHARMM, AMBER, and DREIDING force fields. Setting +coefficients is done in the input data file via the +"read_data"_read_data.html command or in the input script with +commands like "pair_coeff"_pair_coeff.html or +"bond_coeff"_bond_coeff.html. See the "Tools"_Tools.html doc page for +additional tools that can use CHARMM or AMBER to assign force field +coefficients and convert their output into LAMMPS input. + +See "(MacKerell)"_#howto-MacKerell for a description of the CHARMM force +field. See "(Cornell)"_#howto-Cornell for a description of the AMBER force +field. + +:link(charmm,http://www.scripps.edu/brooks) +:link(amber,http://amber.scripps.edu) + +These style choices compute force field formulas that are consistent +with common options in CHARMM or AMBER. See each command's +documentation for the formula it computes. + +"bond_style"_bond_harmonic.html harmonic +"angle_style"_angle_charmm.html charmm +"dihedral_style"_dihedral_charmm.html charmmfsh +"dihedral_style"_dihedral_charmm.html charmm +"pair_style"_pair_charmm.html lj/charmmfsw/coul/charmmfsh +"pair_style"_pair_charmm.html lj/charmmfsw/coul/long +"pair_style"_pair_charmm.html lj/charmm/coul/charmm +"pair_style"_pair_charmm.html lj/charmm/coul/charmm/implicit +"pair_style"_pair_charmm.html lj/charmm/coul/long :ul + +"special_bonds"_special_bonds.html charmm +"special_bonds"_special_bonds.html amber :ul + +NOTE: For CHARMM, newer {charmmfsw} or {charmmfsh} styles were +released in March 2017. We recommend they be used instead of the +older {charmm} styles. See discussion of the differences on the "pair +charmm"_pair_charmm.html and "dihedral charmm"_dihedral_charmm.html +doc pages. + +DREIDING is a generic force field developed by the "Goddard +group"_http://www.wag.caltech.edu at Caltech and is useful for +predicting structures and dynamics of organic, biological and +main-group inorganic molecules. The philosophy in DREIDING is to use +general force constants and geometry parameters based on simple +hybridization considerations, rather than individual force constants +and geometric parameters that depend on the particular combinations of +atoms involved in the bond, angle, or torsion terms. DREIDING has an +"explicit hydrogen bond term"_pair_hbond_dreiding.html to describe +interactions involving a hydrogen atom on very electronegative atoms +(N, O, F). + +See "(Mayo)"_#howto-Mayo for a description of the DREIDING force field + +These style choices compute force field formulas that are consistent +with the DREIDING force field. See each command's +documentation for the formula it computes. + +"bond_style"_bond_harmonic.html harmonic +"bond_style"_bond_morse.html morse :ul + +"angle_style"_angle_harmonic.html harmonic +"angle_style"_angle_cosine.html cosine +"angle_style"_angle_cosine_periodic.html cosine/periodic :ul + +"dihedral_style"_dihedral_charmm.html charmm +"improper_style"_improper_umbrella.html umbrella :ul + +"pair_style"_pair_buck.html buck +"pair_style"_pair_buck.html buck/coul/cut +"pair_style"_pair_buck.html buck/coul/long +"pair_style"_pair_lj.html lj/cut +"pair_style"_pair_lj.html lj/cut/coul/cut +"pair_style"_pair_lj.html lj/cut/coul/long :ul + +"pair_style"_pair_hbond_dreiding.html hbond/dreiding/lj +"pair_style"_pair_hbond_dreiding.html hbond/dreiding/morse :ul + +"special_bonds"_special_bonds.html dreiding :ul + +:line + +:link(howto-MacKerell) +[(MacKerell)] MacKerell, Bashford, Bellott, Dunbrack, Evanseck, Field, +Fischer, Gao, Guo, Ha, et al, J Phys Chem, 102, 3586 (1998). + +:link(howto-Mayo) +[(Mayo)] Mayo, Olfason, Goddard III, J Phys Chem, 94, 8897-8909 +(1990). diff --git a/doc/src/Howto_body.txt b/doc/src/Howto_body.txt new file mode 100644 index 0000000000..cf0a36a972 --- /dev/null +++ b/doc/src/Howto_body.txt @@ -0,0 +1,456 @@ +"Higher level section"_Howto.html - "LAMMPS WWW Site"_lws - "LAMMPS +Documentation"_ld - "LAMMPS Commands"_lc :c + +:link(lws,http://lammps.sandia.gov) +:link(ld,Manual.html) +:link(lc,Section_commands.html#comm) + +:line + +Body particles :h3 + +[Overview:] + +In LAMMPS, body particles are generalized finite-size particles. +Individual body particles can represent complex entities, such as +surface meshes of discrete points, collections of sub-particles, +deformable objects, etc. Note that other kinds of finite-size +spherical and aspherical particles are also supported by LAMMPS, such +as spheres, ellipsoids, line segments, and triangles, but they are +simpler entities that body particles. See "Section +6.14"_Section_howto.html#howto_14 for a general overview of all these +particle types. + +Body particles are used via the "atom_style body"_atom_style.html +command. It takes a body style as an argument. The current body +styles supported by LAMMPS are as follows. The name in the first +column is used as the {bstyle} argument for the "atom_style +body"_atom_style.html command. + +{nparticle} : rigid body with N sub-particles +{rounded/polygon} : 2d polygons with N vertices +{rounded/polyhedron} : 3d polyhedra with N vertices, E edges and F faces :tb(s=:) + +The body style determines what attributes are stored for each body and +thus how they can be used to compute pairwise body/body or +bond/non-body (point particle) interactions. More details of each +style are described below. + +More styles may be added in the future. See the "Modify +body"_Modify_body.html doc page for details on how to add a new body +style to the code. + +:line + +[When to use body particles:] + +You should not use body particles to model a rigid body made of +simpler particles (e.g. point, sphere, ellipsoid, line segment, +triangular particles), if the interaction between pairs of rigid +bodies is just the summation of pairwise interactions between the +simpler particles. LAMMPS already supports this kind of model via the +"fix rigid"_fix_rigid.html command. Any of the numerous pair styles +that compute interactions between simpler particles can be used. The +"fix rigid"_fix_rigid.html command time integrates the motion of the +rigid bodies. All of the standard LAMMPS commands for thermostatting, +adding constraints, performing output, etc will operate as expected on +the simple particles. + +By contrast, when body particles are used, LAMMPS treats an entire +body as a single particle for purposes of computing pairwise +interactions, building neighbor lists, migrating particles between +processors, output of particles to a dump file, etc. This means that +interactions between pairs of bodies or between a body and non-body +(point) particle need to be encoded in an appropriate pair style. If +such a pair style were to mimic the "fix rigid"_fix_rigid.html model, +it would need to loop over the entire collection of interactions +between pairs of simple particles within the two bodies, each time a +single body/body interaction was computed. + +Thus it only makes sense to use body particles and develop such a pair +style, when particle/particle interactions are more complex than what +the "fix rigid"_fix_rigid.html command can already calculate. For +example, consider particles with one or more of the following +attributes: + +represented by a surface mesh +represented by a collection of geometric entities (e.g. planes + spheres) +deformable +internal stress that induces fragmentation :ul + +For these models, the interaction between pairs of particles is likely +to be more complex than the summation of simple pairwise interactions. +An example is contact or frictional forces between particles with +planar surfaces that inter-penetrate. Likewise, the body particle may +store internal state, such as a stress tensor used to compute a +fracture criterion. + +These are additional LAMMPS commands that can be used with body +particles of different styles + +"fix nve/body"_fix_nve_body.html : integrate motion of a body particle in NVE ensemble +"fix nvt/body"_fix_nvt_body.html : ditto for NVT ensemble +"fix npt/body"_fix_npt_body.html : ditto for NPT ensemble +"fix nph/body"_fix_nph_body.html : ditto for NPH ensemble +"compute body/local"_compute_body_local.html : store sub-particle attributes of a body particle +"compute temp/body"_compute_temp_body.html : compute temperature of body particles +"dump local"_dump.html : output sub-particle attributes of a body particle +"dump image"_dump_image.html : output body particle attributes as an image :tb(s=:) + +The pair styles defined for use with specific body styles are listed +in the sections below. + +:line + +[Specifics of body style nparticle:] + +The {nparticle} body style represents body particles as a rigid body +with a variable number N of sub-particles. It is provided as a +vanilla, prototypical example of a body particle, although as +mentioned above, the "fix rigid"_fix_rigid.html command already +duplicates its functionality. + +The atom_style body command for this body style takes two additional +arguments: + +atom_style body nparticle Nmin Nmax +Nmin = minimum # of sub-particles in any body in the system +Nmax = maximum # of sub-particles in any body in the system :pre + +The Nmin and Nmax arguments are used to bound the size of data +structures used internally by each particle. + +When the "read_data"_read_data.html command reads a data file for this +body style, the following information must be provided for each entry +in the {Bodies} section of the data file: + +atom-ID 1 M +N +ixx iyy izz ixy ixz iyz +x1 y1 z1 +... +xN yN zN :pre + +where M = 6 + 3*N, and N is the number of sub-particles in the body +particle. + +The integer line has a single value N. The floating point line(s) +list 6 moments of inertia followed by the coordinates of the N +sub-particles (x1 to zN) as 3N values. These values can be listed on +as many lines as you wish; see the "read_data"_read_data.html command +for more details. + +The 6 moments of inertia (ixx,iyy,izz,ixy,ixz,iyz) should be the +values consistent with the current orientation of the rigid body +around its center of mass. The values are with respect to the +simulation box XYZ axes, not with respect to the principal axes of the +rigid body itself. LAMMPS performs the latter calculation internally. +The coordinates of each sub-particle are specified as its x,y,z +displacement from the center-of-mass of the body particle. The +center-of-mass position of the particle is specified by the x,y,z +values in the {Atoms} section of the data file, as is the total mass +of the body particle. + +The "pair_style body"_pair_body.html command can be used with this +body style to compute body/body and body/non-body interactions. + +For output purposes via the "compute +body/local"_compute_body_local.html and "dump local"_dump.html +commands, this body style produces one datum for each of the N +sub-particles in a body particle. The datum has 3 values: + +1 = x position of sub-particle +2 = y position of sub-particle +3 = z position of sub-particle :pre + +These values are the current position of the sub-particle within the +simulation domain, not a displacement from the center-of-mass (COM) of +the body particle itself. These values are calculated using the +current COM and orientation of the body particle. + +For images created by the "dump image"_dump_image.html command, if the +{body} keyword is set, then each body particle is drawn as a +collection of spheres, one for each sub-particle. The size of each +sphere is determined by the {bflag1} parameter for the {body} keyword. +The {bflag2} argument is ignored. + +:line + +[Specifics of body style rounded/polygon:] + +The {rounded/polygon} body style represents body particles as a 2d +polygon with a variable number of N vertices. This style can only be +used for 2d models; see the "boundary"_boundary.html command. See the +"pair_style body/rounded/polygon" doc page for a diagram of two +squares with rounded circles at the vertices. Special cases for N = 1 +(circle) and N = 2 (rod with rounded ends) can also be specified. + +One use of this body style is for 2d discrete element models, as +described in "Fraige"_#body-Fraige. + +Similar to body style {nparticle}, the atom_style body command for +this body style takes two additional arguments: + +atom_style body rounded/polygon Nmin Nmax +Nmin = minimum # of vertices in any body in the system +Nmax = maximum # of vertices in any body in the system :pre + +The Nmin and Nmax arguments are used to bound the size of data +structures used internally by each particle. + +When the "read_data"_read_data.html command reads a data file for this +body style, the following information must be provided for each entry +in the {Bodies} section of the data file: + +atom-ID 1 M +N +ixx iyy izz ixy ixz iyz +x1 y1 z1 +... +xN yN zN +i j j k k ... +diameter :pre + +where M = 6 + 3*N + 2*N + 1, and N is the number of vertices in the +body particle. + +The integer line has a single value N. The floating point line(s) +list 6 moments of inertia followed by the coordinates of the N +vertices (x1 to zN) as 3N values (with z = 0.0 for each), followed by +2N vertex indices corresponding to the end points of the N edges, +followed by a single diameter value = the rounded diameter of the +circle that surrounds each vertex. The diameter value can be different +for each body particle. These floating-point values can be listed on +as many lines as you wish; see the "read_data"_read_data.html command +for more details. + +The 6 moments of inertia (ixx,iyy,izz,ixy,ixz,iyz) should be the +values consistent with the current orientation of the rigid body +around its center of mass. The values are with respect to the +simulation box XYZ axes, not with respect to the principal axes of the +rigid body itself. LAMMPS performs the latter calculation internally. +The coordinates of each vertex are specified as its x,y,z displacement +from the center-of-mass of the body particle. The center-of-mass +position of the particle is specified by the x,y,z values in the +{Atoms} section of the data file. + +For example, the following information would specify a square particle +whose edge length is sqrt(2) and rounded diameter is 1.0. The +orientation of the square is aligned with the xy coordinate axes which +is consistent with the 6 moments of inertia: ixx iyy izz ixy ixz iyz = +1 1 4 0 0 0. Note that only Izz matters in 2D simulations. + +3 1 27 +4 +1 1 4 0 0 0 +-0.7071 -0.7071 0 +-0.7071 0.7071 0 +0.7071 0.7071 0 +0.7071 -0.7071 0 +0 1 +1 2 +2 3 +3 0 +1.0 :pre + +A rod in 2D, whose length is 4.0, mass 1.0, rounded at two ends +by circles of diameter 0.5, is specified as follows: + +1 1 13 +2 +1 1 1.33333 0 0 0 +-2 0 0 +2 0 0 +0.5 :pre + +A disk, whose diameter is 3.0, mass 1.0, is specified as follows: + +1 1 10 +1 +1 1 4.5 0 0 0 +0 0 0 +3.0 :pre + +The "pair_style body/rounded/polygon"_pair_body_rounded_polygon.html +command can be used with this body style to compute body/body +interactions. The "fix wall/body/polygon"_fix_wall_body_polygon.html +command can be used with this body style to compute the interaction of +body particles with a wall. + +:line + +[Specifics of body style rounded/polyhedron:] + +The {rounded/polyhedron} body style represents body particles as a 3d +polyhedron with a variable number of N vertices, E edges and F faces. +This style can only be used for 3d models; see the +"boundary"_boundary.html command. See the "pair_style +body/rounded/polygon" doc page for a diagram of a two 2d squares with +rounded circles at the vertices. A 3d cube with rounded spheres at +the 8 vertices and 12 rounded edges would be similar. Special cases +for N = 1 (sphere) and N = 2 (rod with rounded ends) can also be +specified. + +This body style is for 3d discrete element models, as described in +"Wang"_#body-Wang. + +Similar to body style {rounded/polygon}, the atom_style body command +for this body style takes two additional arguments: + +atom_style body rounded/polyhedron Nmin Nmax +Nmin = minimum # of vertices in any body in the system +Nmax = maximum # of vertices in any body in the system :pre + +The Nmin and Nmax arguments are used to bound the size of data +structures used internally by each particle. + +When the "read_data"_read_data.html command reads a data file for this +body style, the following information must be provided for each entry +in the {Bodies} section of the data file: + +atom-ID 3 M +N E F +ixx iyy izz ixy ixz iyz +x1 y1 z1 +... +xN yN zN +0 1 +1 2 +2 3 +... +0 1 2 -1 +0 2 3 -1 +... +1 2 3 4 +diameter :pre + +where M = 6 + 3*N + 2*E + 4*F + 1, and N is the number of vertices in +the body particle, E = number of edges, F = number of faces. + +The integer line has three values: number of vertices (N), number of +edges (E) and number of faces (F). The floating point line(s) list 6 +moments of inertia followed by the coordinates of the N vertices (x1 +to zN) as 3N values, followed by 2N vertex indices corresponding to +the end points of the E edges, then 4*F vertex indices defining F +faces. The last value is the diameter value = the rounded diameter of +the sphere that surrounds each vertex. The diameter value can be +different for each body particle. These floating-point values can be +listed on as many lines as you wish; see the +"read_data"_read_data.html command for more details. Because the +maxmimum vertices per face is hard-coded to be 4 +(i.e. quadrilaterals), faces with more than 4 vertices need to be +split into triangles or quadrilaterals. For triangular faces, the +last vertex index should be set to -1. + +The ordering of the 4 vertices within a face should follow +the right-hand rule so that the normal vector of the face points +outwards from the center of mass. + +The 6 moments of inertia (ixx,iyy,izz,ixy,ixz,iyz) should be the +values consistent with the current orientation of the rigid body +around its center of mass. The values are with respect to the +simulation box XYZ axes, not with respect to the principal axes of the +rigid body itself. LAMMPS performs the latter calculation internally. +The coordinates of each vertex are specified as its x,y,z displacement +from the center-of-mass of the body particle. The center-of-mass +position of the particle is specified by the x,y,z values in the +{Atoms} section of the data file. + +For example, the following information would specify a cubic particle +whose edge length is 2.0 and rounded diameter is 0.5. +The orientation of the cube is aligned with the xyz coordinate axes +which is consistent with the 6 moments of inertia: ixx iyy izz ixy ixz +iyz = 0.667 0.667 0.667 0 0 0. + +1 3 79 +8 12 6 +0.667 0.667 0.667 0 0 0 +1 1 1 +1 -1 1 +-1 -1 1 +-1 1 1 +1 1 -1 +1 -1 -1 +-1 -1 -1 +-1 1 -1 +0 1 +1 2 +2 3 +3 0 +4 5 +5 6 +6 7 +7 4 +0 4 +1 5 +2 6 +3 7 +0 1 2 3 +4 5 6 7 +0 1 5 4 +1 2 6 5 +2 3 7 6 +3 0 4 7 +0.5 :pre + +A rod in 3D, whose length is 4.0, mass 1.0 and rounded at two ends +by circles of diameter 0.5, is specified as follows: + +1 1 13 +2 +0 1.33333 1.33333 0 0 0 +-2 0 0 +2 0 0 +0.5 :pre + +A sphere whose diameter is 3.0 and mass 1.0, is specified as follows: + +1 1 10 +1 +0.9 0.9 0.9 0 0 0 +0 0 0 +3.0 :pre + +The "pair_style +body/rounded/polhedron"_pair_body_rounded_polyhedron.html command can +be used with this body style to compute body/body interactions. The +"fix wall/body/polyhedron"_fix_wall_body_polygon.html command can be +used with this body style to compute the interaction of body particles +with a wall. + +:line + +For output purposes via the "compute +body/local"_compute_body_local.html and "dump local"_dump.html +commands, this body style produces one datum for each of the N +sub-particles in a body particle. The datum has 3 values: + +1 = x position of vertex +2 = y position of vertex +3 = z position of vertex :pre + +These values are the current position of the vertex within the +simulation domain, not a displacement from the center-of-mass (COM) of +the body particle itself. These values are calculated using the +current COM and orientation of the body particle. + +For images created by the "dump image"_dump_image.html command, if the +{body} keyword is set, then each body particle is drawn as a polygon +consisting of N line segments. Note that the line segments are drawn +between the N vertices, which does not correspond exactly to the +physical extent of the body (because the "pair_style +rounded/polygon"_pair_body_rounded_polygon.html defines finite-size +spheres at those point and the line segments between the spheres are +tangent to the spheres). The drawn diameter of each line segment is +determined by the {bflag1} parameter for the {body} keyword. The +{bflag2} argument is ignored. + +:line + +:link(body-Fraige) +[(Fraige)] F. Y. Fraige, P. A. Langston, A. J. Matchett, J. Dodds, +Particuology, 6, 455 (2008). + +:link(body-Wang) +[(Wang)] J. Wang, H. S. Yu, P. A. Langston, F. Y. Fraige, Granular +Matter, 13, 1 (2011). diff --git a/doc/src/Howto_chunk.txt b/doc/src/Howto_chunk.txt new file mode 100644 index 0000000000..9d757b2729 --- /dev/null +++ b/doc/src/Howto_chunk.txt @@ -0,0 +1,166 @@ +"Higher level section"_Howto.html - "LAMMPS WWW Site"_lws - "LAMMPS +Documentation"_ld - "LAMMPS Commands"_lc :c + +:link(lws,http://lammps.sandia.gov) +:link(ld,Manual.html) +:link(lc,Section_commands.html#comm) + +:line + +Use chunks to calculate system properties :h3 + +In LAMMS, "chunks" are collections of atoms, as defined by the +"compute chunk/atom"_compute_chunk_atom.html command, which assigns +each atom to a chunk ID (or to no chunk at all). The number of chunks +and the assignment of chunk IDs to atoms can be static or change over +time. Examples of "chunks" are molecules or spatial bins or atoms +with similar values (e.g. coordination number or potential energy). + +The per-atom chunk IDs can be used as input to two other kinds of +commands, to calculate various properties of a system: + +"fix ave/chunk"_fix_ave_chunk.html +any of the "compute */chunk"_compute.html commands :ul + +Here, each of the 3 kinds of chunk-related commands is briefly +overviewed. Then some examples are given of how to compute different +properties with chunk commands. + +Compute chunk/atom command: :h4 + +This compute can assign atoms to chunks of various styles. Only atoms +in the specified group and optional specified region are assigned to a +chunk. Here are some possible chunk definitions: + +atoms in same molecule | chunk ID = molecule ID | +atoms of same atom type | chunk ID = atom type | +all atoms with same atom property (charge, radius, etc) | chunk ID = output of compute property/atom | +atoms in same cluster | chunk ID = output of "compute cluster/atom"_compute_cluster_atom.html command | +atoms in same spatial bin | chunk ID = bin ID | +atoms in same rigid body | chunk ID = molecule ID used to define rigid bodies | +atoms with similar potential energy | chunk ID = output of "compute pe/atom"_compute_pe_atom.html | +atoms with same local defect structure | chunk ID = output of "compute centro/atom"_compute_centro_atom.html or "compute coord/atom"_compute_coord_atom.html command :tb(s=|,c=2) + +Note that chunk IDs are integer values, so for atom properties or +computes that produce a floating point value, they will be truncated +to an integer. You could also use the compute in a variable that +scales the floating point value to spread it across multiple integers. + +Spatial bins can be of various kinds, e.g. 1d bins = slabs, 2d bins = +pencils, 3d bins = boxes, spherical bins, cylindrical bins. + +This compute also calculates the number of chunks {Nchunk}, which is +used by other commands to tally per-chunk data. {Nchunk} can be a +static value or change over time (e.g. the number of clusters). The +chunk ID for an individual atom can also be static (e.g. a molecule +ID), or dynamic (e.g. what spatial bin an atom is in as it moves). + +Note that this compute allows the per-atom output of other +"computes"_compute.html, "fixes"_fix.html, and +"variables"_variable.html to be used to define chunk IDs for each +atom. This means you can write your own compute or fix to output a +per-atom quantity to use as chunk ID. See the "Modify"_Modify.html +doc pages for info on how to do this. You can also define a "per-atom +variable"_variable.html in the input script that uses a formula to +generate a chunk ID for each atom. + +Fix ave/chunk command: :h4 + +This fix takes the ID of a "compute +chunk/atom"_compute_chunk_atom.html command as input. For each chunk, +it then sums one or more specified per-atom values over the atoms in +each chunk. The per-atom values can be any atom property, such as +velocity, force, charge, potential energy, kinetic energy, stress, +etc. Additional keywords are defined for per-chunk properties like +density and temperature. More generally any per-atom value generated +by other "computes"_compute.html, "fixes"_fix.html, and "per-atom +variables"_variable.html, can be summed over atoms in each chunk. + +Similar to other averaging fixes, this fix allows the summed per-chunk +values to be time-averaged in various ways, and output to a file. The +fix produces a global array as output with one row of values per +chunk. + +Compute */chunk commands: :h4 + +Currently the following computes operate on chunks of atoms to produce +per-chunk values. + +"compute com/chunk"_compute_com_chunk.html +"compute gyration/chunk"_compute_gyration_chunk.html +"compute inertia/chunk"_compute_inertia_chunk.html +"compute msd/chunk"_compute_msd_chunk.html +"compute property/chunk"_compute_property_chunk.html +"compute temp/chunk"_compute_temp_chunk.html +"compute torque/chunk"_compute_vcm_chunk.html +"compute vcm/chunk"_compute_vcm_chunk.html :ul + +They each take the ID of a "compute +chunk/atom"_compute_chunk_atom.html command as input. As their names +indicate, they calculate the center-of-mass, radius of gyration, +moments of inertia, mean-squared displacement, temperature, torque, +and velocity of center-of-mass for each chunk of atoms. The "compute +property/chunk"_compute_property_chunk.html command can tally the +count of atoms in each chunk and extract other per-chunk properties. + +The reason these various calculations are not part of the "fix +ave/chunk command"_fix_ave_chunk.html, is that each requires a more +complicated operation than simply summing and averaging over per-atom +values in each chunk. For example, many of them require calculation +of a center of mass, which requires summing mass*position over the +atoms and then dividing by summed mass. + +All of these computes produce a global vector or global array as +output, wih one or more values per chunk. They can be used +in various ways: + +As input to the "fix ave/time"_fix_ave_time.html command, which can +write the values to a file and optionally time average them. :ulb,l + +As input to the "fix ave/histo"_fix_ave_histo.html command to +histogram values across chunks. E.g. a histogram of cluster sizes or +molecule diffusion rates. :l + +As input to special functions of "equal-style +variables"_variable.html, like sum() and max(). E.g. to find the +largest cluster or fastest diffusing molecule. :l +:ule + +Example calculations with chunks :h4 + +Here are examples using chunk commands to calculate various +properties: + +(1) Average velocity in each of 1000 2d spatial bins: + +compute cc1 all chunk/atom bin/2d x 0.0 0.1 y lower 0.01 units reduced +fix 1 all ave/chunk 100 10 1000 cc1 vx vy file tmp.out :pre + +(2) Temperature in each spatial bin, after subtracting a flow +velocity: + +compute cc1 all chunk/atom bin/2d x 0.0 0.1 y lower 0.1 units reduced +compute vbias all temp/profile 1 0 0 y 10 +fix 1 all ave/chunk 100 10 1000 cc1 temp bias vbias file tmp.out :pre + +(3) Center of mass of each molecule: + +compute cc1 all chunk/atom molecule +compute myChunk all com/chunk cc1 +fix 1 all ave/time 100 1 100 c_myChunk\[*\] file tmp.out mode vector :pre + +(4) Total force on each molecule and ave/max across all molecules: + +compute cc1 all chunk/atom molecule +fix 1 all ave/chunk 1000 1 1000 cc1 fx fy fz file tmp.out +variable xave equal ave(f_1\[2\]) +variable xmax equal max(f_1\[2\]) +thermo 1000 +thermo_style custom step temp v_xave v_xmax :pre + +(5) Histogram of cluster sizes: + +compute cluster all cluster/atom 1.0 +compute cc1 all chunk/atom c_cluster compress yes +compute size all property/chunk cc1 count +fix 1 all ave/histo 100 1 100 0 20 20 c_size mode vector ave running beyond ignore file tmp.histo :pre diff --git a/doc/src/Howto_coreshell.txt b/doc/src/Howto_coreshell.txt new file mode 100644 index 0000000000..273568418b --- /dev/null +++ b/doc/src/Howto_coreshell.txt @@ -0,0 +1,253 @@ +"Higher level section"_Howto.html - "LAMMPS WWW Site"_lws - "LAMMPS +Documentation"_ld - "LAMMPS Commands"_lc :c + +:link(lws,http://lammps.sandia.gov) +:link(ld,Manual.html) +:link(lc,Section_commands.html#comm) + +:line + +Adiabatic core/shell model :h3 + +The adiabatic core-shell model by "Mitchell and +Fincham"_#MitchellFincham is a simple method for adding polarizability +to a system. In order to mimic the electron shell of an ion, a +satellite particle is attached to it. This way the ions are split into +a core and a shell where the latter is meant to react to the +electrostatic environment inducing polarizability. See the "Howto +polarizable"_Howto_polarizable.html doc page for a discussion of all +the polarizable models available in LAMMPS. + +Technically, shells are attached to the cores by a spring force f = +k*r where k is a parametrized spring constant and r is the distance +between the core and the shell. The charges of the core and the shell +add up to the ion charge, thus q(ion) = q(core) + q(shell). This +setup introduces the ion polarizability (alpha) given by +alpha = q(shell)^2 / k. In a +similar fashion the mass of the ion is distributed on the core and the +shell with the core having the larger mass. + +To run this model in LAMMPS, "atom_style"_atom_style.html {full} can +be used since atom charge and bonds are needed. Each kind of +core/shell pair requires two atom types and a bond type. The core and +shell of a core/shell pair should be bonded to each other with a +harmonic bond that provides the spring force. For example, a data file +for NaCl, as found in examples/coreshell, has this format: + +432 atoms # core and shell atoms +216 bonds # number of core/shell springs :pre + +4 atom types # 2 cores and 2 shells for Na and Cl +2 bond types :pre + +0.0 24.09597 xlo xhi +0.0 24.09597 ylo yhi +0.0 24.09597 zlo zhi :pre + +Masses # core/shell mass ratio = 0.1 :pre + +1 20.690784 # Na core +2 31.90500 # Cl core +3 2.298976 # Na shell +4 3.54500 # Cl shell :pre + +Atoms :pre + +1 1 2 1.5005 0.00000000 0.00000000 0.00000000 # core of core/shell pair 1 +2 1 4 -2.5005 0.00000000 0.00000000 0.00000000 # shell of core/shell pair 1 +3 2 1 1.5056 4.01599500 4.01599500 4.01599500 # core of core/shell pair 2 +4 2 3 -0.5056 4.01599500 4.01599500 4.01599500 # shell of core/shell pair 2 +(...) :pre + +Bonds # Bond topology for spring forces :pre + +1 2 1 2 # spring for core/shell pair 1 +2 2 3 4 # spring for core/shell pair 2 +(...) :pre + +Non-Coulombic (e.g. Lennard-Jones) pairwise interactions are only +defined between the shells. Coulombic interactions are defined +between all cores and shells. If desired, additional bonds can be +specified between cores. + +The "special_bonds"_special_bonds.html command should be used to +turn-off the Coulombic interaction within core/shell pairs, since that +interaction is set by the bond spring. This is done using the +"special_bonds"_special_bonds.html command with a 1-2 weight = 0.0, +which is the default value. It needs to be considered whether one has +to adjust the "special_bonds"_special_bonds.html weighting according +to the molecular topology since the interactions of the shells are +bypassed over an extra bond. + +Note that this core/shell implementation does not require all ions to +be polarized. One can mix core/shell pairs and ions without a +satellite particle if desired. + +Since the core/shell model permits distances of r = 0.0 between the +core and shell, a pair style with a "cs" suffix needs to be used to +implement a valid long-range Coulombic correction. Several such pair +styles are provided in the CORESHELL package. See "this doc +page"_pair_cs.html for details. All of the core/shell enabled pair +styles require the use of a long-range Coulombic solver, as specified +by the "kspace_style"_kspace_style.html command. Either the PPPM or +Ewald solvers can be used. + +For the NaCL example problem, these pair style and bond style settings +are used: + +pair_style born/coul/long/cs 20.0 20.0 +pair_coeff * * 0.0 1.000 0.00 0.00 0.00 +pair_coeff 3 3 487.0 0.23768 0.00 1.05 0.50 #Na-Na +pair_coeff 3 4 145134.0 0.23768 0.00 6.99 8.70 #Na-Cl +pair_coeff 4 4 405774.0 0.23768 0.00 72.40 145.40 #Cl-Cl :pre + +bond_style harmonic +bond_coeff 1 63.014 0.0 +bond_coeff 2 25.724 0.0 :pre + +When running dynamics with the adiabatic core/shell model, the +following issues should be considered. The relative motion of +the core and shell particles corresponds to the polarization, +hereby an instantaneous relaxation of the shells is approximated +and a fast core/shell spring frequency ensures a nearly constant +internal kinetic energy during the simulation. +Thermostats can alter this polarization behaviour, by scaling the +internal kinetic energy, meaning the shell will not react freely to +its electrostatic environment. +Therefore it is typically desirable to decouple the relative motion of +the core/shell pair, which is an imaginary degree of freedom, from the +real physical system. To do that, the "compute +temp/cs"_compute_temp_cs.html command can be used, in conjunction with +any of the thermostat fixes, such as "fix nvt"_fix_nh.html or "fix +langevin"_fix_langevin. This compute uses the center-of-mass velocity +of the core/shell pairs to calculate a temperature, and insures that +velocity is what is rescaled for thermostatting purposes. This +compute also works for a system with both core/shell pairs and +non-polarized ions (ions without an attached satellite particle). The +"compute temp/cs"_compute_temp_cs.html command requires input of two +groups, one for the core atoms, another for the shell atoms. +Non-polarized ions which might also be included in the treated system +should not be included into either of these groups, they are taken +into account by the {group-ID} (2nd argument) of the compute. The +groups can be defined using the "group {type}"_group.html command. +Note that to perform thermostatting using this definition of +temperature, the "fix modify temp"_fix_modify.html command should be +used to assign the compute to the thermostat fix. Likewise the +"thermo_modify temp"_thermo_modify.html command can be used to make +this temperature be output for the overall system. + +For the NaCl example, this can be done as follows: + +group cores type 1 2 +group shells type 3 4 +compute CSequ all temp/cs cores shells +fix thermoberendsen all temp/berendsen 1427 1427 0.4 # thermostat for the true physical system +fix thermostatequ all nve # integrator as needed for the berendsen thermostat +fix_modify thermoberendsen temp CSequ +thermo_modify temp CSequ # output of center-of-mass derived temperature :pre + +The pressure for the core/shell system is computed via the regular +LAMMPS convention by "treating the cores and shells as individual +particles"_#MitchellFincham2. For the thermo output of the pressure +as well as for the application of a barostat, it is necessary to +use an additional "pressure"_compute_pressure compute based on the +default "temperature"_compute_temp and specifying it as a second +argument in "fix modify"_fix_modify.html and +"thermo_modify"_thermo_modify.html resulting in: + +(...) +compute CSequ all temp/cs cores shells +compute thermo_press_lmp all pressure thermo_temp # pressure for individual particles +thermo_modify temp CSequ press thermo_press_lmp # modify thermo to regular pressure +fix press_bar all npt temp 300 300 0.04 iso 0 0 0.4 +fix_modify press_bar temp CSequ press thermo_press_lmp # pressure modification for correct kinetic scalar :pre + +If "compute temp/cs"_compute_temp_cs.html is used, the decoupled +relative motion of the core and the shell should in theory be +stable. However numerical fluctuation can introduce a small +momentum to the system, which is noticable over long trajectories. +Therefore it is recommendable to use the "fix +momentum"_fix_momentum.html command in combination with "compute +temp/cs"_compute_temp_cs.html when equilibrating the system to +prevent any drift. + +When initializing the velocities of a system with core/shell pairs, it +is also desirable to not introduce energy into the relative motion of +the core/shell particles, but only assign a center-of-mass velocity to +the pairs. This can be done by using the {bias} keyword of the +"velocity create"_velocity.html command and assigning the "compute +temp/cs"_compute_temp_cs.html command to the {temp} keyword of the +"velocity"_velocity.html command, e.g. + +velocity all create 1427 134 bias yes temp CSequ +velocity all scale 1427 temp CSequ :pre + +To maintain the correct polarizability of the core/shell pairs, the +kinetic energy of the internal motion shall remain nearly constant. +Therefore the choice of spring force and mass ratio need to ensure +much faster relative motion of the 2 atoms within the core/shell pair +than their center-of-mass velocity. This allows the shells to +effectively react instantaneously to the electrostatic environment and +limits energy transfer to or from the core/shell oscillators. +This fast movement also dictates the timestep that can be used. + +The primary literature of the adiabatic core/shell model suggests that +the fast relative motion of the core/shell pairs only allows negligible +energy transfer to the environment. +The mentioned energy transfer will typically lead to a small drift +in total energy over time. This internal energy can be monitored +using the "compute chunk/atom"_compute_chunk_atom.html and "compute +temp/chunk"_compute_temp_chunk.html commands. The internal kinetic +energies of each core/shell pair can then be summed using the sum() +special function of the "variable"_variable.html command. Or they can +be time/averaged and output using the "fix ave/time"_fix_ave_time.html +command. To use these commands, each core/shell pair must be defined +as a "chunk". If each core/shell pair is defined as its own molecule, +the molecule ID can be used to define the chunks. If cores are bonded +to each other to form larger molecules, the chunks can be identified +by the "fix property/atom"_fix_property_atom.html via assigning a +core/shell ID to each atom using a special field in the data file read +by the "read_data"_read_data.html command. This field can then be +accessed by the "compute property/atom"_compute_property_atom.html +command, to use as input to the "compute +chunk/atom"_compute_chunk_atom.html command to define the core/shell +pairs as chunks. + +For example if core/shell pairs are the only molecules: + +read_data NaCl_CS_x0.1_prop.data +compute prop all property/atom molecule +compute cs_chunk all chunk/atom c_prop +compute cstherm all temp/chunk cs_chunk temp internal com yes cdof 3.0 # note the chosen degrees of freedom for the core/shell pairs +fix ave_chunk all ave/time 10 1 10 c_cstherm file chunk.dump mode vector :pre + +For example if core/shell pairs and other molecules are present: + +fix csinfo all property/atom i_CSID # property/atom command +read_data NaCl_CS_x0.1_prop.data fix csinfo NULL CS-Info # atom property added in the data-file +compute prop all property/atom i_CSID +(...) :pre + +The additional section in the date file would be formatted like this: + +CS-Info # header of additional section :pre + +1 1 # column 1 = atom ID, column 2 = core/shell ID +2 1 +3 2 +4 2 +5 3 +6 3 +7 4 +8 4 +(...) :pre + +:line + +:link(MitchellFincham) +[(Mitchell and Fincham)] Mitchell, Fincham, J Phys Condensed Matter, +5, 1031-1038 (1993). + +:link(MitchellFincham2) +[(Fincham)] Fincham, Mackrodt and Mitchell, J Phys Condensed Matter, +6, 393-404 (1994). diff --git a/doc/src/Howto_couple.txt b/doc/src/Howto_couple.txt new file mode 100644 index 0000000000..ec45bd1290 --- /dev/null +++ b/doc/src/Howto_couple.txt @@ -0,0 +1,105 @@ +"Higher level section"_Howto.html - "LAMMPS WWW Site"_lws - "LAMMPS +Documentation"_ld - "LAMMPS Commands"_lc :c + +:link(lws,http://lammps.sandia.gov) +:link(ld,Manual.html) +:link(lc,Section_commands.html#comm) + +:line + +Coupling LAMMPS to other codes :h3 + +LAMMPS is designed to allow it to be coupled to other codes. For +example, a quantum mechanics code might compute forces on a subset of +atoms and pass those forces to LAMMPS. Or a continuum finite element +(FE) simulation might use atom positions as boundary conditions on FE +nodal points, compute a FE solution, and return interpolated forces on +MD atoms. + +LAMMPS can be coupled to other codes in at least 3 ways. Each has +advantages and disadvantages, which you'll have to think about in the +context of your application. + +(1) Define a new "fix"_fix.html command that calls the other code. In +this scenario, LAMMPS is the driver code. During its timestepping, +the fix is invoked, and can make library calls to the other code, +which has been linked to LAMMPS as a library. This is the way the +"POEMS"_poems package that performs constrained rigid-body motion on +groups of atoms is hooked to LAMMPS. See the "fix +poems"_fix_poems.html command for more details. See the +"Modify"_Modify.html doc pages for info on how to add a new fix to +LAMMPS. + +:link(poems,http://www.rpi.edu/~anderk5/lab) + +(2) Define a new LAMMPS command that calls the other code. This is +conceptually similar to method (1), but in this case LAMMPS and the +other code are on a more equal footing. Note that now the other code +is not called during the timestepping of a LAMMPS run, but between +runs. The LAMMPS input script can be used to alternate LAMMPS runs +with calls to the other code, invoked via the new command. The +"run"_run.html command facilitates this with its {every} option, which +makes it easy to run a few steps, invoke the command, run a few steps, +invoke the command, etc. + +In this scenario, the other code can be called as a library, as in +(1), or it could be a stand-alone code, invoked by a system() call +made by the command (assuming your parallel machine allows one or more +processors to start up another program). In the latter case the +stand-alone code could communicate with LAMMPS thru files that the +command writes and reads. + +See the "Modify command"_Modify_command.html doc page for info on how +to add a new command to LAMMPS. + +(3) Use LAMMPS as a library called by another code. In this case the +other code is the driver and calls LAMMPS as needed. Or a wrapper +code could link and call both LAMMPS and another code as libraries. +Again, the "run"_run.html command has options that allow it to be +invoked with minimal overhead (no setup or clean-up) if you wish to do +multiple short runs, driven by another program. + +Examples of driver codes that call LAMMPS as a library are included in +the examples/COUPLE directory of the LAMMPS distribution; see +examples/COUPLE/README for more details: + +simple: simple driver programs in C++ and C which invoke LAMMPS as a +library :ulb,l + +lammps_quest: coupling of LAMMPS and "Quest"_quest, to run classical +MD with quantum forces calculated by a density functional code :l + +lammps_spparks: coupling of LAMMPS and "SPPARKS"_spparks, to couple +a kinetic Monte Carlo model for grain growth using MD to calculate +strain induced across grain boundaries :l +:ule + +:link(quest,http://dft.sandia.gov/Quest) +:link(spparks,http://www.sandia.gov/~sjplimp/spparks.html) + +"This section"_Section_start.html#start_5 of the documentation +describes how to build LAMMPS as a library. Once this is done, you +can interface with LAMMPS either via C++, C, Fortran, or Python (or +any other language that supports a vanilla C-like interface). For +example, from C++ you could create one (or more) "instances" of +LAMMPS, pass it an input script to process, or execute individual +commands, all by invoking the correct class methods in LAMMPS. From C +or Fortran you can make function calls to do the same things. See the +"Python"_Python.html doc pages for a description of the Python wrapper +provided with LAMMPS that operates through the LAMMPS library +interface. + +The files src/library.cpp and library.h contain the C-style interface +to LAMMPS. See the "Howto library"_Howto_library.html doc page for a +description of the interface and how to extend it for your needs. + +Note that the lammps_open() function that creates an instance of +LAMMPS takes an MPI communicator as an argument. This means that +instance of LAMMPS will run on the set of processors in the +communicator. Thus the calling code can run LAMMPS on all or a subset +of processors. For example, a wrapper script might decide to +alternate between LAMMPS and another code, allowing them both to run +on all the processors. Or it might allocate half the processors to +LAMMPS and half to the other code and run both codes simultaneously +before syncing them up periodically. Or it might instantiate multiple +instances of LAMMPS to perform different calculations. diff --git a/doc/src/Howto_diffusion.txt b/doc/src/Howto_diffusion.txt new file mode 100644 index 0000000000..e0e16e1042 --- /dev/null +++ b/doc/src/Howto_diffusion.txt @@ -0,0 +1,31 @@ +"Higher level section"_Howto.html - "LAMMPS WWW Site"_lws - "LAMMPS +Documentation"_ld - "LAMMPS Commands"_lc :c + +:link(lws,http://lammps.sandia.gov) +:link(ld,Manual.html) +:link(lc,Section_commands.html#comm) + +:line + +Calculate a diffusion coefficient :h3 + +The diffusion coefficient D of a material can be measured in at least +2 ways using various options in LAMMPS. See the examples/DIFFUSE +directory for scripts that implement the 2 methods discussed here for +a simple Lennard-Jones fluid model. + +The first method is to measure the mean-squared displacement (MSD) of +the system, via the "compute msd"_compute_msd.html command. The slope +of the MSD versus time is proportional to the diffusion coefficient. +The instantaneous MSD values can be accumulated in a vector via the +"fix vector"_fix_vector.html command, and a line fit to the vector to +compute its slope via the "variable slope"_variable.html function, and +thus extract D. + +The second method is to measure the velocity auto-correlation function +(VACF) of the system, via the "compute vacf"_compute_vacf.html +command. The time-integral of the VACF is proportional to the +diffusion coefficient. The instantaneous VACF values can be +accumulated in a vector via the "fix vector"_fix_vector.html command, +and time integrated via the "variable trap"_variable.html function, +and thus extract D. diff --git a/doc/src/Howto_dispersion.txt b/doc/src/Howto_dispersion.txt new file mode 100644 index 0000000000..000f45076d --- /dev/null +++ b/doc/src/Howto_dispersion.txt @@ -0,0 +1,108 @@ +"Higher level section"_Howto.html - "LAMMPS WWW Site"_lws - "LAMMPS +Documentation"_ld - "LAMMPS Commands"_lc :c + +:link(lws,http://lammps.sandia.gov) +:link(ld,Manual.html) +:link(lc,Section_commands.html#comm) + +:line + +Long-raage dispersion settings :h3 + +The PPPM method computes interactions by splitting the pair potential +into two parts, one of which is computed in a normal pairwise fashion, +the so-called real-space part, and one of which is computed using the +Fourier transform, the so called reciprocal-space or kspace part. For +both parts, the potential is not computed exactly but is approximated. +Thus, there is an error in both parts of the computation, the +real-space and the kspace error. The just mentioned facts are true +both for the PPPM for Coulomb as well as dispersion interactions. The +deciding difference - and also the reason why the parameters for +pppm/disp have to be selected with more care - is the impact of the +errors on the results: The kspace error of the PPPM for Coulomb and +dispersion interaction and the real-space error of the PPPM for +Coulomb interaction have the character of noise. In contrast, the +real-space error of the PPPM for dispersion has a clear physical +interpretation: the underprediction of cohesion. As a consequence, the +real-space error has a much stronger effect than the kspace error on +simulation results for pppm/disp. Parameters must thus be chosen in a +way that this error is much smaller than the kspace error. + +When using pppm/disp and not making any specifications on the PPPM +parameters via the kspace modify command, parameters will be tuned +such that the real-space error and the kspace error are equal. This +will result in simulations that are either inaccurate or slow, both of +which is not desirable. For selecting parameters for the pppm/disp +that provide fast and accurate simulations, there are two approaches, +which both have their up- and downsides. + +The first approach is to set desired real-space an kspace accuracies +via the {kspace_modify force/disp/real} and {kspace_modify +force/disp/kspace} commands. Note that the accuracies have to be +specified in force units and are thus dependent on the chosen unit +settings. For real units, 0.0001 and 0.002 seem to provide reasonable +accurate and efficient computations for the real-space and kspace +accuracies. 0.002 and 0.05 work well for most systems using lj +units. PPPM parameters will be generated based on the desired +accuracies. The upside of this approach is that it usually provides a +good set of parameters and will work for both the {kspace_modify diff +ad} and {kspace_modify diff ik} options. The downside of the method +is that setting the PPPM parameters will take some time during the +initialization of the simulation. + +The second approach is to set the parameters for the pppm/disp +explicitly using the {kspace_modify mesh/disp}, {kspace_modify +order/disp}, and {kspace_modify gewald/disp} commands. This approach +requires a more experienced user who understands well the impact of +the choice of parameters on the simulation accuracy and +performance. This approach provides a fast initialization of the +simulation. However, it is sensitive to errors: A combination of +parameters that will perform well for one system might result in +far-from-optimal conditions for other simulations. For example, +parameters that provide accurate and fast computations for +all-atomistic force fields can provide insufficient accuracy or +united-atomistic force fields (which is related to that the latter +typically have larger dispersion coefficients). + +To avoid inaccurate or inefficient simulations, the pppm/disp stops +simulations with an error message if no action is taken to control the +PPPM parameters. If the automatic parameter generation is desired and +real-space and kspace accuracies are desired to be equal, this error +message can be suppressed using the {kspace_modify disp/auto yes} +command. + +A reasonable approach that combines the upsides of both methods is to +make the first run using the {kspace_modify force/disp/real} and +{kspace_modify force/disp/kspace} commands, write down the PPPM +parameters from the outut, and specify these parameters using the +second approach in subsequent runs (which have the same composition, +force field, and approximately the same volume). + +Concerning the performance of the pppm/disp there are two more things +to consider. The first is that when using the pppm/disp, the cutoff +parameter does no longer affect the accuracy of the simulation +(subject to that gewald/disp is adjusted when changing the cutoff). +The performance can thus be increased by examining different values +for the cutoff parameter. A lower bound for the cutoff is only set by +the truncation error of the repulsive term of pair potentials. + +The second is that the mixing rule of the pair style has an impact on +the computation time when using the pppm/disp. Fastest computations +are achieved when using the geometric mixing rule. Using the +arithmetic mixing rule substantially increases the computational cost. +The computational overhead can be reduced using the {kspace_modify +mix/disp geom} and {kspace_modify splittol} commands. The first +command simply enforces geometric mixing of the dispersion +coefficients in kspace computations. This introduces some error in +the computations but will also significantly speed-up the +simulations. The second keyword sets the accuracy with which the +dispersion coefficients are approximated using a matrix factorization +approach. This may result in better accuracy then using the first +command, but will usually also not provide an equally good increase of +efficiency. + +Finally, pppm/disp can also be used when no mixing rules apply. +This can be achieved using the {kspace_modify mix/disp none} command. +Note that the code does not check automatically whether any mixing +rule is fulfilled. If mixing rules do not apply, the user will have +to specify this command explicitly. diff --git a/doc/src/Howto_drude.txt b/doc/src/Howto_drude.txt new file mode 100644 index 0000000000..e9c30db772 --- /dev/null +++ b/doc/src/Howto_drude.txt @@ -0,0 +1,77 @@ +"Higher level section"_Howto.html - "LAMMPS WWW Site"_lws - "LAMMPS +Documentation"_ld - "LAMMPS Commands"_lc :c + +:link(lws,http://lammps.sandia.gov) +:link(ld,Manual.html) +:link(lc,Section_commands.html#comm) + +:line + +Drude induced dipoles :h3 + +The thermalized Drude model represents induced dipoles by a pair of +charges (the core atom and the Drude particle) connected by a harmonic +spring. See the "Howto polarizable"_Howto_polarizable.html doc page +for a discussion of all the polarizable models available in LAMMPS. + +The Drude model has a number of features aimed at its use in +molecular systems ("Lamoureux and Roux"_#howto-Lamoureux): + +Thermostating of the additional degrees of freedom associated with the +induced dipoles at very low temperature, in terms of the reduced +coordinates of the Drude particles with respect to their cores. This +makes the trajectory close to that of relaxed induced dipoles. :ulb,l + +Consistent definition of 1-2 to 1-4 neighbors. A core-Drude particle +pair represents a single (polarizable) atom, so the special screening +factors in a covalent structure should be the same for the core and +the Drude particle. Drude particles have to inherit the 1-2, 1-3, 1-4 +special neighbor relations from their respective cores. :l + +Stabilization of the interactions between induced dipoles. Drude +dipoles on covalently bonded atoms interact too strongly due to the +short distances, so an atom may capture the Drude particle of a +neighbor, or the induced dipoles within the same molecule may align +too much. To avoid this, damping at short range can be done by Thole +functions (for which there are physical grounds). This Thole damping +is applied to the point charges composing the induced dipole (the +charge of the Drude particle and the opposite charge on the core, not +to the total charge of the core atom). :l,ule + +A detailed tutorial covering the usage of Drude induced dipoles in +LAMMPS is on the "Howto drude2e"_Howto_drude2.html doc page. + +As with the core-shell model, the cores and Drude particles should +appear in the data file as standard atoms. The same holds for the +springs between them, which are described by standard harmonic bonds. +The nature of the atoms (core, Drude particle or non-polarizable) is +specified via the "fix drude"_fix_drude.html command. The special +list of neighbors is automatically refactored to account for the +equivalence of core and Drude particles as regards special 1-2 to 1-4 +screening. It may be necessary to use the {extra/special/per/atom} +keyword of the "read_data"_read_data.html command. If using "fix +shake"_fix_shake.html, make sure no Drude particle is in this fix +group. + +There are two ways to thermostat the Drude particles at a low +temperature: use either "fix langevin/drude"_fix_langevin_drude.html +for a Langevin thermostat, or "fix +drude/transform/*"_fix_drude_transform.html for a Nose-Hoover +thermostat. The former requires use of the command "comm_modify vel +yes"_comm_modify.html. The latter requires two separate integration +fixes like {nvt} or {npt}. The correct temperatures of the reduced +degrees of freedom can be calculated using the "compute +temp/drude"_compute_temp_drude.html. This requires also to use the +command {comm_modify vel yes}. + +Short-range damping of the induced dipole interactions can be achieved +using Thole functions through the "pair style +thole"_pair_thole.html in "pair_style hybrid/overlay"_pair_hybrid.html +with a Coulomb pair style. It may be useful to use {coul/long/cs} or +similar from the CORESHELL package if the core and Drude particle come +too close, which can cause numerical issues. + +:line + +:link(howto-Lamoureux) +[(Lamoureux and Roux)] G. Lamoureux, B. Roux, J. Chem. Phys 119, 3025 (2003) diff --git a/doc/src/tutorial_drude.txt b/doc/src/Howto_drude2.txt similarity index 100% rename from doc/src/tutorial_drude.txt rename to doc/src/Howto_drude2.txt diff --git a/doc/src/Howto_elastic.txt b/doc/src/Howto_elastic.txt new file mode 100644 index 0000000000..4dda13fa53 --- /dev/null +++ b/doc/src/Howto_elastic.txt @@ -0,0 +1,47 @@ +"Higher level section"_Howto.html - "LAMMPS WWW Site"_lws - "LAMMPS +Documentation"_ld - "LAMMPS Commands"_lc :c + +:link(lws,http://lammps.sandia.gov) +:link(ld,Manual.html) +:link(lc,Section_commands.html#comm) + +:line + +Calculate elastic constants :h3 + +Elastic constants characterize the stiffness of a material. The formal +definition is provided by the linear relation that holds between the +stress and strain tensors in the limit of infinitesimal deformation. +In tensor notation, this is expressed as s_ij = C_ijkl * e_kl, where +the repeated indices imply summation. s_ij are the elements of the +symmetric stress tensor. e_kl are the elements of the symmetric strain +tensor. C_ijkl are the elements of the fourth rank tensor of elastic +constants. In three dimensions, this tensor has 3^4=81 elements. Using +Voigt notation, the tensor can be written as a 6x6 matrix, where C_ij +is now the derivative of s_i w.r.t. e_j. Because s_i is itself a +derivative w.r.t. e_i, it follows that C_ij is also symmetric, with at +most 7*6/2 = 21 distinct elements. + +At zero temperature, it is easy to estimate these derivatives by +deforming the simulation box in one of the six directions using the +"change_box"_change_box.html command and measuring the change in the +stress tensor. A general-purpose script that does this is given in the +examples/elastic directory described on the "Examples"_Examples.html +doc page. + +Calculating elastic constants at finite temperature is more +challenging, because it is necessary to run a simulation that perfoms +time averages of differential properties. One way to do this is to +measure the change in average stress tensor in an NVT simulations when +the cell volume undergoes a finite deformation. In order to balance +the systematic and statistical errors in this method, the magnitude of +the deformation must be chosen judiciously, and care must be taken to +fully equilibrate the deformed cell before sampling the stress +tensor. Another approach is to sample the triclinic cell fluctuations +that occur in an NPT simulation. This method can also be slow to +converge and requires careful post-processing "(Shinoda)"_#Shinoda1 + +:line + +:link(Shinoda1) +[(Shinoda)] Shinoda, Shiga, and Mikami, Phys Rev B, 69, 134103 (2004). diff --git a/doc/src/tutorial_github.txt b/doc/src/Howto_github.txt similarity index 98% rename from doc/src/tutorial_github.txt rename to doc/src/Howto_github.txt index fc261bdb95..191242205e 100644 --- a/doc/src/tutorial_github.txt +++ b/doc/src/Howto_github.txt @@ -25,8 +25,8 @@ or improvements to LAMMPS, as it significantly reduces the amount of work required by the LAMMPS developers. Consequently, creating a pull request will increase your chances to have your contribution included and will reduce the time until the integration is complete. For more -information on the requirements to have your code included in LAMMPS, -see the "Modify contribute"_Modify_contribute.html doc page. +information on the requirements to have your code included into LAMMPS +please see the "Modify contribute"_Modify_contribute.html doc page. :line @@ -124,7 +124,7 @@ unrelated feature, you should switch branches! After everything is done, add the files to the branch and commit them: - $ git add doc/src/tutorial_github.txt + $ git add doc/src/Howto_github.txt $ git add doc/src/JPG/tutorial*.png :pre IMPORTANT NOTE: Do not use {git commit -a} (or {git add -A}). The -a @@ -318,7 +318,7 @@ Because the changes are OK with us, we are going to merge by clicking on Now, since in the meantime our local text for the tutorial also changed, we need to pull Axel's change back into our branch, and merge them: - $ git add tutorial_github.txt + $ git add Howto_github.txt $ git add JPG/tutorial_reverse_pull_request*.png $ git commit -m "Updated text and images on reverse pull requests" $ git pull :pre @@ -331,7 +331,7 @@ With Axel's changes merged in and some final text updates, our feature branch is now perfect as far as we are concerned, so we are going to commit and push again: - $ git add tutorial_github.txt + $ git add Howto_github.txt $ git add JPG/tutorial_reverse_pull_request6.png $ git commit -m "Merged Axel's suggestions and updated text" $ git push git@github.com:Pakketeretet2/lammps :pre diff --git a/doc/src/Howto_granular.txt b/doc/src/Howto_granular.txt new file mode 100644 index 0000000000..cfa01bcb63 --- /dev/null +++ b/doc/src/Howto_granular.txt @@ -0,0 +1,57 @@ +"Higher level section"_Howto.html - "LAMMPS WWW Site"_lws - "LAMMPS +Documentation"_ld - "LAMMPS Commands"_lc :c + +:link(lws,http://lammps.sandia.gov) +:link(ld,Manual.html) +:link(lc,Section_commands.html#comm) + +:line + +Granular models :h3 + +Granular system are composed of spherical particles with a diameter, +as opposed to point particles. This means they have an angular +velocity and torque can be imparted to them to cause them to rotate. + +To run a simulation of a granular model, you will want to use +the following commands: + +"atom_style sphere"_atom_style.html +"fix nve/sphere"_fix_nve_sphere.html +"fix gravity"_fix_gravity.html :ul + +This compute + +"compute erotate/sphere"_compute_erotate_sphere.html :ul + +calculates rotational kinetic energy which can be "output with +thermodynamic info"_Howto_output.html. + +Use one of these 3 pair potentials, which compute forces and torques +between interacting pairs of particles: + +"pair_style"_pair_style.html gran/history +"pair_style"_pair_style.html gran/no_history +"pair_style"_pair_style.html gran/hertzian :ul + +These commands implement fix options specific to granular systems: + +"fix freeze"_fix_freeze.html +"fix pour"_fix_pour.html +"fix viscous"_fix_viscous.html +"fix wall/gran"_fix_wall_gran.html :ul + +The fix style {freeze} zeroes both the force and torque of frozen +atoms, and should be used for granular system instead of the fix style +{setforce}. + +For computational efficiency, you can eliminate needless pairwise +computations between frozen atoms by using this command: + +"neigh_modify"_neigh_modify.html exclude :ul + +NOTE: By default, for 2d systems, granular particles are still modeled +as 3d spheres, not 2d discs (circles), meaning their moment of inertia +will be the same as in 3d. If you wish to model granular particles in +2d as 2d discs, see the note on this topic on the "Howto 2d"_Howto_2d +doc page, where 2d simulations are discussed. diff --git a/doc/src/Howto_kappa.txt b/doc/src/Howto_kappa.txt new file mode 100644 index 0000000000..949901f21a --- /dev/null +++ b/doc/src/Howto_kappa.txt @@ -0,0 +1,90 @@ +"Higher level section"_Howto.html - "LAMMPS WWW Site"_lws - "LAMMPS +Documentation"_ld - "LAMMPS Commands"_lc :c + +:link(lws,http://lammps.sandia.gov) +:link(ld,Manual.html) +:link(lc,Section_commands.html#comm) + +:line + +Calculate thermal conductivity :h3 + +The thermal conductivity kappa of a material can be measured in at +least 4 ways using various options in LAMMPS. See the examples/KAPPA +directory for scripts that implement the 4 methods discussed here for +a simple Lennard-Jones fluid model. Also, see the "Howto +viscosity"_Howto_viscosity.html doc page for an analogous discussion +for viscosity. + +The thermal conductivity tensor kappa is a measure of the propensity +of a material to transmit heat energy in a diffusive manner as given +by Fourier's law + +J = -kappa grad(T) + +where J is the heat flux in units of energy per area per time and +grad(T) is the spatial gradient of temperature. The thermal +conductivity thus has units of energy per distance per time per degree +K and is often approximated as an isotropic quantity, i.e. as a +scalar. + +The first method is to setup two thermostatted regions at opposite +ends of a simulation box, or one in the middle and one at the end of a +periodic box. By holding the two regions at different temperatures +with a "thermostatting fix"_Howto_thermostat.html, the energy added to +the hot region should equal the energy subtracted from the cold region +and be proportional to the heat flux moving between the regions. See +the papers by "Ikeshoji and Hafskjold"_#howto-Ikeshoji and +"Wirnsberger et al"_#howto-Wirnsberger for details of this idea. Note +that thermostatting fixes such as "fix nvt"_fix_nh.html, "fix +langevin"_fix_langevin.html, and "fix +temp/rescale"_fix_temp_rescale.html store the cumulative energy they +add/subtract. + +Alternatively, as a second method, the "fix heat"_fix_heat.html or +"fix ehex"_fix_ehex.html commands can be used in place of thermostats +on each of two regions to add/subtract specified amounts of energy to +both regions. In both cases, the resulting temperatures of the two +regions can be monitored with the "compute temp/region" command and +the temperature profile of the intermediate region can be monitored +with the "fix ave/chunk"_fix_ave_chunk.html and "compute +ke/atom"_compute_ke_atom.html commands. + +The third method is to perform a reverse non-equilibrium MD simulation +using the "fix thermal/conductivity"_fix_thermal_conductivity.html +command which implements the rNEMD algorithm of Muller-Plathe. +Kinetic energy is swapped between atoms in two different layers of the +simulation box. This induces a temperature gradient between the two +layers which can be monitored with the "fix +ave/chunk"_fix_ave_chunk.html and "compute +ke/atom"_compute_ke_atom.html commands. The fix tallies the +cumulative energy transfer that it performs. See the "fix +thermal/conductivity"_fix_thermal_conductivity.html command for +details. + +The fourth method is based on the Green-Kubo (GK) formula which +relates the ensemble average of the auto-correlation of the heat flux +to kappa. The heat flux can be calculated from the fluctuations of +per-atom potential and kinetic energies and per-atom stress tensor in +a steady-state equilibrated simulation. This is in contrast to the +two preceding non-equilibrium methods, where energy flows continuously +between hot and cold regions of the simulation box. + +The "compute heat/flux"_compute_heat_flux.html command can calculate +the needed heat flux and describes how to implement the Green_Kubo +formalism using additional LAMMPS commands, such as the "fix +ave/correlate"_fix_ave_correlate.html command to calculate the needed +auto-correlation. See the doc page for the "compute +heat/flux"_compute_heat_flux.html command for an example input script +that calculates the thermal conductivity of solid Ar via the GK +formalism. + +:line + +:link(howto-Ikeshoji) +[(Ikeshoji)] Ikeshoji and Hafskjold, Molecular Physics, 81, 251-261 +(1994). + +:link(howto-Wirnsberger) +[(Wirnsberger)] Wirnsberger, Frenkel, and Dellago, J Chem Phys, 143, 124104 +(2015). diff --git a/doc/src/Howto_library.txt b/doc/src/Howto_library.txt new file mode 100644 index 0000000000..b15aadd214 --- /dev/null +++ b/doc/src/Howto_library.txt @@ -0,0 +1,208 @@ +"Higher level section"_Howto.html - "LAMMPS WWW Site"_lws - "LAMMPS +Documentation"_ld - "LAMMPS Commands"_lc :c + +:link(lws,http://lammps.sandia.gov) +:link(ld,Manual.html) +:link(lc,Section_commands.html#comm) + +:line + +Library interface to LAMMPS :h3 + +As described in "Section 2.5"_Section_start.html#start_5, LAMMPS can +be built as a library, so that it can be called by another code, used +in a "coupled manner"_Howto_couple.html with other codes, or driven +through a "Python interface"_Python.html. + +All of these methodologies use a C-style interface to LAMMPS that is +provided in the files src/library.cpp and src/library.h. The +functions therein have a C-style argument list, but contain C++ code +you could write yourself in a C++ application that was invoking LAMMPS +directly. The C++ code in the functions illustrates how to invoke +internal LAMMPS operations. Note that LAMMPS classes are defined +within a LAMMPS namespace (LAMMPS_NS) if you use them from another C++ +application. + +The examples/COUPLE and python/examples directories have example C++ +and C and Python codes which show how a driver code can link to LAMMPS +as a library, run LAMMPS on a subset of processors, grab data from +LAMMPS, change it, and put it back into LAMMPS. + +The file src/library.cpp contains the following functions for creating +and destroying an instance of LAMMPS and sending it commands to +execute. See the documentation in the src/library.cpp file for +details. + +NOTE: You can write code for additional functions as needed to define +how your code talks to LAMMPS and add them to src/library.cpp and +src/library.h, as well as to the "Python interface"_Python.html. The +added functions can access or change any internal LAMMPS data you +wish. + +void lammps_open(int, char **, MPI_Comm, void **) +void lammps_open_no_mpi(int, char **, void **) +void lammps_close(void *) +int lammps_version(void *) +void lammps_file(void *, char *) +char *lammps_command(void *, char *) +void lammps_commands_list(void *, int, char **) +void lammps_commands_string(void *, char *) +void lammps_free(void *) :pre + +The lammps_open() function is used to initialize LAMMPS, passing in a +list of strings as if they were "command-line +arguments"_Section_start.html#start_6 when LAMMPS is run in +stand-alone mode from the command line, and a MPI communicator for +LAMMPS to run under. It returns a ptr to the LAMMPS object that is +created, and which is used in subsequent library calls. The +lammps_open() function can be called multiple times, to create +multiple instances of LAMMPS. + +LAMMPS will run on the set of processors in the communicator. This +means the calling code can run LAMMPS on all or a subset of +processors. For example, a wrapper script might decide to alternate +between LAMMPS and another code, allowing them both to run on all the +processors. Or it might allocate half the processors to LAMMPS and +half to the other code and run both codes simultaneously before +syncing them up periodically. Or it might instantiate multiple +instances of LAMMPS to perform different calculations. + +The lammps_open_no_mpi() function is similar except that no MPI +communicator is passed from the caller. Instead, MPI_COMM_WORLD is +used to instantiate LAMMPS, and MPI is initialized if necessary. + +The lammps_close() function is used to shut down an instance of LAMMPS +and free all its memory. + +The lammps_version() function can be used to determined the specific +version of the underlying LAMMPS code. This is particularly useful +when loading LAMMPS as a shared library via dlopen(). The code using +the library interface can than use this information to adapt to +changes to the LAMMPS command syntax between versions. The returned +LAMMPS version code is an integer (e.g. 2 Sep 2015 results in +20150902) that grows with every new LAMMPS version. + +The lammps_file(), lammps_command(), lammps_commands_list(), and +lammps_commands_string() functions are used to pass one or more +commands to LAMMPS to execute, the same as if they were coming from an +input script. + +Via these functions, the calling code can read or generate a series of +LAMMPS commands one or multiple at a time and pass it thru the library +interface to setup a problem and then run it in stages. The caller +can interleave the command function calls with operations it performs, +calls to extract information from or set information within LAMMPS, or +calls to another code's library. + +The lammps_file() function passes the filename of an input script. +The lammps_command() function passes a single command as a string. +The lammps_commands_list() function passes multiple commands in a +char** list. In both lammps_command() and lammps_commands_list(), +individual commands may or may not have a trailing newline. The +lammps_commands_string() function passes multiple commands +concatenated into one long string, separated by newline characters. +In both lammps_commands_list() and lammps_commands_string(), a single +command can be spread across multiple lines, if the last printable +character of all but the last line is "&", the same as if the lines +appeared in an input script. + +The lammps_free() function is a clean-up function to free memory that +the library allocated previously via other function calls. See +comments in src/library.cpp file for which other functions need this +clean-up. + +The file src/library.cpp also contains these functions for extracting +information from LAMMPS and setting value within LAMMPS. Again, see +the documentation in the src/library.cpp file for details, including +which quantities can be queried by name: + +int lammps_extract_setting(void *, char *) +void *lammps_extract_global(void *, char *) +void lammps_extract_box(void *, double *, double *, + double *, double *, double *, int *, int *) +void *lammps_extract_atom(void *, char *) +void *lammps_extract_compute(void *, char *, int, int) +void *lammps_extract_fix(void *, char *, int, int, int, int) +void *lammps_extract_variable(void *, char *, char *) :pre + +The extract_setting() function returns info on the size +of data types (e.g. 32-bit or 64-bit atom IDs) used +by the LAMMPS executable (a compile-time choice). + +The other extract functions return a pointer to various global or +per-atom quantities stored in LAMMPS or to values calculated by a +compute, fix, or variable. The pointer returned by the +extract_global() function can be used as a permanent reference to a +value which may change. For the extract_atom() method, see the +extract() method in the src/atom.cpp file for a list of valid per-atom +properties. New names could easily be added if the property you want +is not listed. For the other extract functions, the underlying +storage may be reallocated as LAMMPS runs, so you need to re-call the +function to assure a current pointer or returned value(s). + +double lammps_get_thermo(void *, char *) +int lammps_get_natoms(void *) :pre + +int lammps_set_variable(void *, char *, char *) +void lammps_reset_box(void *, double *, double *, double, double, double) :pre + +The lammps_get_thermo() function returns the current value of a thermo +keyword as a double precision value. + +The lammps_get_natoms() function returns the total number of atoms in +the system and can be used by the caller to allocate memory for the +lammps_gather_atoms() and lammps_scatter_atoms() functions. + +The lammps_set_variable() function can set an existing string-style +variable to a new string value, so that subsequent LAMMPS commands can +access the variable. + +The lammps_reset_box() function resets the size and shape of the +simulation box, e.g. as part of restoring a previously extracted and +saved state of a simulation. + +void lammps_gather_atoms(void *, char *, int, int, void *) +void lammps_gather_atoms_concat(void *, char *, int, int, void *) +void lammps_gather_atoms_subset(void *, char *, int, int, int, int *, void *) +void lammps_scatter_atoms(void *, char *, int, int, void *) +void lammps_scatter_atoms_subset(void *, char *, int, int, int, int *, void *) :pre + +void lammps_create_atoms(void *, int, tagint *, int *, double *, double *, + imageint *, int) :pre + +The gather functions collect peratom info of the requested type (atom +coords, atom types, forces, etc) from all processors, and returns the +same vector of values to each callling processor. The scatter +functions do the inverse. They distribute a vector of peratom values, +passed by all calling processors, to invididual atoms, which may be +owned by different processos. + +The lammps_gather_atoms() function does this for all N atoms in the +system, ordered by atom ID, from 1 to N. The +lammps_gather_atoms_concat() function does it for all N atoms, but +simply concatenates the subset of atoms owned by each processor. The +resulting vector is not ordered by atom ID. Atom IDs can be requetsed +by the same function if the caller needs to know the ordering. The +lammps_gather_subset() function allows the caller to request values +for only a subset of atoms (identified by ID). +For all 3 gather function, per-atom image flags can be retrieved in 2 ways. +If the count is specified as 1, they are returned +in a packed format with all three image flags stored in a single integer. +If the count is specified as 3, the values are unpacked into xyz flags +by the library before returning them. + +The lammps_scatter_atoms() function takes a list of values for all N +atoms in the system, ordered by atom ID, from 1 to N, and assigns +those values to each atom in the system. The +lammps_scatter_atoms_subset() function takes a subset of IDs as an +argument and only scatters those values to the owning atoms. + +The lammps_create_atoms() function takes a list of N atoms as input +with atom types and coords (required), an optionally atom IDs and +velocities and image flags. It uses the coords of each atom to assign +it as a new atom to the processor that owns it. This function is +useful to add atoms to a simulation or (in tandem with +lammps_reset_box()) to restore a previously extracted and saved state +of a simulation. Additional properties for the new atoms can then be +assigned via the lammps_scatter_atoms() or lammps_extract_atom() +functions. diff --git a/doc/src/Howto_manifold.txt b/doc/src/Howto_manifold.txt new file mode 100644 index 0000000000..c9bb1ce57f --- /dev/null +++ b/doc/src/Howto_manifold.txt @@ -0,0 +1,41 @@ +"LAMMPS WWW Site"_lws - "LAMMPS Documentation"_ld - "LAMMPS Commands"_lc :c + +:link(lws,http://lammps.sandia.gov) +:link(ld,Manual.html) +:link(lc,Section_commands.html#comm) + +:line + +Manifolds (surfaces) :h3 + +[Overview:] + +This doc page is not about a LAMMPS input script command, but about +manifolds, which are generalized surfaces, as defined and used by the +USER-MANIFOLD package, to track particle motion on the manifolds. See +the src/USER-MANIFOLD/README file for more details about the package +and its commands. + +Below is a list of currently supported manifolds by the USER-MANIFOLD +package, their parameters and a short description of them. The +parameters listed here are in the same order as they should be passed +to the relevant fixes. + +{manifold} @ {parameters} @ {equation} @ {description} +cylinder @ R @ x^2 + y^2 - R^2 = 0 @ Cylinder along z-axis, axis going through (0,0,0) +cylinder_dent @ R l a @ x^2 + y^2 - r(z)^2 = 0, r(x) = R if | z | > l, r(z) = R - a*(1 + cos(z/l))/2 otherwise @ A cylinder with a dent around z = 0 +dumbbell @ a A B c @ -( x^2 + y^2 ) + (a^2 - z^2/c^2) * ( 1 + (A*sin(B*z^2))^4) = 0 @ A dumbbell +ellipsoid @ a b c @ (x/a)^2 + (y/b)^2 + (z/c)^2 = 0 @ An ellipsoid +gaussian_bump @ A l rc1 rc2 @ if( x < rc1) -z + A * exp( -x^2 / (2 l^2) ); else if( x < rc2 ) -z + a + b*x + c*x^2 + d*x^3; else z @ A Gaussian bump at x = y = 0, smoothly tapered to a flat plane z = 0. +plane @ a b c x0 y0 z0 @ a*(x-x0) + b*(y-y0) + c*(z-z0) = 0 @ A plane with normal (a,b,c) going through point (x0,y0,z0) +plane_wiggle @ a w @ z - a*sin(w*x) = 0 @ A plane with a sinusoidal modulation on z along x. +sphere @ R @ x^2 + y^2 + z^2 - R^2 = 0 @ A sphere of radius R +supersphere @ R q @ | x |^q + | y |^q + | z |^q - R^q = 0 @ A supersphere of hyperradius R +spine @ a, A, B, B2, c @ -(x^2 + y^2) + (a^2 - z^2/f(z)^2)*(1 + (A*sin(g(z)*z^2))^4), f(z) = c if z > 0, 1 otherwise; g(z) = B if z > 0, B2 otherwise @ An approximation to a dendtritic spine +spine_two @ a, A, B, B2, c @ -(x^2 + y^2) + (a^2 - z^2/f(z)^2)*(1 + (A*sin(g(z)*z^2))^2), f(z) = c if z > 0, 1 otherwise; g(z) = B if z > 0, B2 otherwise @ Another approximation to a dendtritic spine +thylakoid @ wB LB lB @ Various, see "(Paquay)"_#Paquay1 @ A model grana thylakoid consisting of two block-like compartments connected by a bridge of width wB, length LB and taper length lB +torus @ R r @ (R - sqrt( x^2 + y^2 ) )^2 + z^2 - r^2 @ A torus with large radius R and small radius r, centered on (0,0,0) :tb(s=@) + +:link(Paquay1) +[(Paquay)] Paquay and Kusters, Biophys. J., 110, 6, (2016). +preprint available at "arXiv:1411.3019"_http://arxiv.org/abs/1411.3019/. diff --git a/doc/src/Howto_multiple.txt b/doc/src/Howto_multiple.txt new file mode 100644 index 0000000000..3516debb71 --- /dev/null +++ b/doc/src/Howto_multiple.txt @@ -0,0 +1,95 @@ +"Higher level section"_Howto.html - "LAMMPS WWW Site"_lws - "LAMMPS +Documentation"_ld - "LAMMPS Commands"_lc :c + +:link(lws,http://lammps.sandia.gov) +:link(ld,Manual.html) +:link(lc,Section_commands.html#comm) + +:line + +Run multiple simulations from one input script :h3 + +This can be done in several ways. See the documentation for +individual commands for more details on how these examples work. + +If "multiple simulations" means continue a previous simulation for +more timesteps, then you simply use the "run"_run.html command +multiple times. For example, this script + +units lj +atom_style atomic +read_data data.lj +run 10000 +run 10000 +run 10000 +run 10000 +run 10000 :pre + +would run 5 successive simulations of the same system for a total of +50,000 timesteps. + +If you wish to run totally different simulations, one after the other, +the "clear"_clear.html command can be used in between them to +re-initialize LAMMPS. For example, this script + +units lj +atom_style atomic +read_data data.lj +run 10000 +clear +units lj +atom_style atomic +read_data data.lj.new +run 10000 :pre + +would run 2 independent simulations, one after the other. + +For large numbers of independent simulations, you can use +"variables"_variable.html and the "next"_next.html and +"jump"_jump.html commands to loop over the same input script +multiple times with different settings. For example, this +script, named in.polymer + +variable d index run1 run2 run3 run4 run5 run6 run7 run8 +shell cd $d +read_data data.polymer +run 10000 +shell cd .. +clear +next d +jump in.polymer :pre + +would run 8 simulations in different directories, using a data.polymer +file in each directory. The same concept could be used to run the +same system at 8 different temperatures, using a temperature variable +and storing the output in different log and dump files, for example + +variable a loop 8 +variable t index 0.8 0.85 0.9 0.95 1.0 1.05 1.1 1.15 +log log.$a +read data.polymer +velocity all create $t 352839 +fix 1 all nvt $t $t 100.0 +dump 1 all atom 1000 dump.$a +run 100000 +clear +next t +next a +jump in.polymer :pre + +All of the above examples work whether you are running on 1 or +multiple processors, but assumed you are running LAMMPS on a single +partition of processors. LAMMPS can be run on multiple partitions via +the "-partition" command-line switch as described in "this +section"_Section_start.html#start_6 of the manual. + +In the last 2 examples, if LAMMPS were run on 3 partitions, the same +scripts could be used if the "index" and "loop" variables were +replaced with {universe}-style variables, as described in the +"variable"_variable.html command. Also, the "next t" and "next a" +commands would need to be replaced with a single "next a t" command. +With these modifications, the 8 simulations of each script would run +on the 3 partitions one after the other until all were finished. +Initially, 3 simulations would be started simultaneously, one on each +partition. When one finished, that partition would then start +the 4th simulation, and so forth, until all 8 were completed. diff --git a/doc/src/Howto_nemd.txt b/doc/src/Howto_nemd.txt new file mode 100644 index 0000000000..efb3a5cd73 --- /dev/null +++ b/doc/src/Howto_nemd.txt @@ -0,0 +1,48 @@ +"Higher level section"_Howto.html - "LAMMPS WWW Site"_lws - "LAMMPS +Documentation"_ld - "LAMMPS Commands"_lc :c + +:link(lws,http://lammps.sandia.gov) +:link(ld,Manual.html) +:link(lc,Section_commands.html#comm) + +:line + +NEMD simulations :h3 + +Non-equilibrium molecular dynamics or NEMD simulations are typically +used to measure a fluid's rheological properties such as viscosity. +In LAMMPS, such simulations can be performed by first setting up a +non-orthogonal simulation box (see the preceding Howto section). + +A shear strain can be applied to the simulation box at a desired +strain rate by using the "fix deform"_fix_deform.html command. The +"fix nvt/sllod"_fix_nvt_sllod.html command can be used to thermostat +the sheared fluid and integrate the SLLOD equations of motion for the +system. Fix nvt/sllod uses "compute +temp/deform"_compute_temp_deform.html to compute a thermal temperature +by subtracting out the streaming velocity of the shearing atoms. The +velocity profile or other properties of the fluid can be monitored via +the "fix ave/chunk"_fix_ave_chunk.html command. + +As discussed in the previous section on non-orthogonal simulation +boxes, the amount of tilt or skew that can be applied is limited by +LAMMPS for computational efficiency to be 1/2 of the parallel box +length. However, "fix deform"_fix_deform.html can continuously strain +a box by an arbitrary amount. As discussed in the "fix +deform"_fix_deform.html command, when the tilt value reaches a limit, +the box is flipped to the opposite limit which is an equivalent tiling +of periodic space. The strain rate can then continue to change as +before. In a long NEMD simulation these box re-shaping events may +occur many times. + +In a NEMD simulation, the "remap" option of "fix +deform"_fix_deform.html should be set to "remap v", since that is what +"fix nvt/sllod"_fix_nvt_sllod.html assumes to generate a velocity +profile consistent with the applied shear strain rate. + +An alternative method for calculating viscosities is provided via the +"fix viscosity"_fix_viscosity.html command. + +NEMD simulations can also be used to measure transport properties of a fluid +through a pore or channel. Simulations of steady-state flow can be performed +using the "fix flow/gauss"_fix_flow_gauss.html command. diff --git a/doc/src/Howto_output.txt b/doc/src/Howto_output.txt new file mode 100644 index 0000000000..ed2a78ee19 --- /dev/null +++ b/doc/src/Howto_output.txt @@ -0,0 +1,307 @@ +"Higher level section"_Howto.html - "LAMMPS WWW Site"_lws - "LAMMPS +Documentation"_ld - "LAMMPS Commands"_lc :c + +:link(lws,http://lammps.sandia.gov) +:link(ld,Manual.html) +:link(lc,Section_commands.html#comm) + +:line + +Output from LAMMPS (thermo, dumps, computes, fixes, variables) :h3 + +There are four basic kinds of LAMMPS output: + +"Thermodynamic output"_thermo_style.html, which is a list +of quantities printed every few timesteps to the screen and logfile. :ulb,l + +"Dump files"_dump.html, which contain snapshots of atoms and various +per-atom values and are written at a specified frequency. :l + +Certain fixes can output user-specified quantities to files: "fix +ave/time"_fix_ave_time.html for time averaging, "fix +ave/chunk"_fix_ave_chunk.html for spatial or other averaging, and "fix +print"_fix_print.html for single-line output of +"variables"_variable.html. Fix print can also output to the +screen. :l + +"Restart files"_restart.html. :l +:ule + +A simulation prints one set of thermodynamic output and (optionally) +restart files. It can generate any number of dump files and fix +output files, depending on what "dump"_dump.html and "fix"_fix.html +commands you specify. + +As discussed below, LAMMPS gives you a variety of ways to determine +what quantities are computed and printed when the thermodynamics, +dump, or fix commands listed above perform output. Throughout this +discussion, note that users can also "add their own computes and fixes +to LAMMPS"_Modify.html which can then generate values that can then be +output with these commands. + +The following sub-sections discuss different LAMMPS command related +to output and the kind of data they operate on and produce: + +"Global/per-atom/local data"_#global +"Scalar/vector/array data"_#scalar +"Thermodynamic output"_#thermo +"Dump file output"_#dump +"Fixes that write output files"_#fixoutput +"Computes that process output quantities"_#computeoutput +"Fixes that process output quantities"_#fixprocoutput +"Computes that generate values to output"_#compute +"Fixes that generate values to output"_#fix +"Variables that generate values to output"_#variable +"Summary table of output options and data flow between commands"_#table :ul + +Global/per-atom/local data :h4,link(global) + +Various output-related commands work with three different styles of +data: global, per-atom, or local. A global datum is one or more +system-wide values, e.g. the temperature of the system. A per-atom +datum is one or more values per atom, e.g. the kinetic energy of each +atom. Local datums are calculated by each processor based on the +atoms it owns, but there may be zero or more per atom, e.g. a list of +bond distances. + +Scalar/vector/array data :h4,link(scalar) + +Global, per-atom, and local datums can each come in three kinds: a +single scalar value, a vector of values, or a 2d array of values. The +doc page for a "compute" or "fix" or "variable" that generates data +will specify both the style and kind of data it produces, e.g. a +per-atom vector. + +When a quantity is accessed, as in many of the output commands +discussed below, it can be referenced via the following bracket +notation, where ID in this case is the ID of a compute. The leading +"c_" would be replaced by "f_" for a fix, or "v_" for a variable: + +c_ID | entire scalar, vector, or array +c_ID\[I\] | one element of vector, one column of array +c_ID\[I\]\[J\] | one element of array :tb(s=|) + +In other words, using one bracket reduces the dimension of the data +once (vector -> scalar, array -> vector). Using two brackets reduces +the dimension twice (array -> scalar). Thus a command that uses +scalar values as input can typically also process elements of a vector +or array. + +Thermodynamic output :h4,link(thermo) + +The frequency and format of thermodynamic output is set by the +"thermo"_thermo.html, "thermo_style"_thermo_style.html, and +"thermo_modify"_thermo_modify.html commands. The +"thermo_style"_thermo_style.html command also specifies what values +are calculated and written out. Pre-defined keywords can be specified +(e.g. press, etotal, etc). Three additional kinds of keywords can +also be specified (c_ID, f_ID, v_name), where a "compute"_compute.html +or "fix"_fix.html or "variable"_variable.html provides the value to be +output. In each case, the compute, fix, or variable must generate +global values for input to the "thermo_style custom"_dump.html +command. + +Note that thermodynamic output values can be "extensive" or +"intensive". The former scale with the number of atoms in the system +(e.g. total energy), the latter do not (e.g. temperature). The +setting for "thermo_modify norm"_thermo_modify.html determines whether +extensive quantities are normalized or not. Computes and fixes +produce either extensive or intensive values; see their individual doc +pages for details. "Equal-style variables"_variable.html produce only +intensive values; you can include a division by "natoms" in the +formula if desired, to make an extensive calculation produce an +intensive result. + +Dump file output :h4,link(dump) + +Dump file output is specified by the "dump"_dump.html and +"dump_modify"_dump_modify.html commands. There are several +pre-defined formats (dump atom, dump xtc, etc). + +There is also a "dump custom"_dump.html format where the user +specifies what values are output with each atom. Pre-defined atom +attributes can be specified (id, x, fx, etc). Three additional kinds +of keywords can also be specified (c_ID, f_ID, v_name), where a +"compute"_compute.html or "fix"_fix.html or "variable"_variable.html +provides the values to be output. In each case, the compute, fix, or +variable must generate per-atom values for input to the "dump +custom"_dump.html command. + +There is also a "dump local"_dump.html format where the user specifies +what local values to output. A pre-defined index keyword can be +specified to enumerate the local values. Two additional kinds of +keywords can also be specified (c_ID, f_ID), where a +"compute"_compute.html or "fix"_fix.html or "variable"_variable.html +provides the values to be output. In each case, the compute or fix +must generate local values for input to the "dump local"_dump.html +command. + +Fixes that write output files :h4,link(fixoutput) + +Several fixes take various quantities as input and can write output +files: "fix ave/time"_fix_ave_time.html, "fix +ave/chunk"_fix_ave_chunk.html, "fix ave/histo"_fix_ave_histo.html, +"fix ave/correlate"_fix_ave_correlate.html, and "fix +print"_fix_print.html. + +The "fix ave/time"_fix_ave_time.html command enables direct output to +a file and/or time-averaging of global scalars or vectors. The user +specifies one or more quantities as input. These can be global +"compute"_compute.html values, global "fix"_fix.html values, or +"variables"_variable.html of any style except the atom style which +produces per-atom values. Since a variable can refer to keywords used +by the "thermo_style custom"_thermo_style.html command (like temp or +press) and individual per-atom values, a wide variety of quantities +can be time averaged and/or output in this way. If the inputs are one +or more scalar values, then the fix generate a global scalar or vector +of output. If the inputs are one or more vector values, then the fix +generates a global vector or array of output. The time-averaged +output of this fix can also be used as input to other output commands. + +The "fix ave/chunk"_fix_ave_chunk.html command enables direct output +to a file of chunk-averaged per-atom quantities like those output in +dump files. Chunks can represent spatial bins or other collections of +atoms, e.g. individual molecules. The per-atom quantities can be atom +density (mass or number) or atom attributes such as position, +velocity, force. They can also be per-atom quantities calculated by a +"compute"_compute.html, by a "fix"_fix.html, or by an atom-style +"variable"_variable.html. The chunk-averaged output of this fix can +also be used as input to other output commands. + +The "fix ave/histo"_fix_ave_histo.html command enables direct output +to a file of histogrammed quantities, which can be global or per-atom +or local quantities. The histogram output of this fix can also be +used as input to other output commands. + +The "fix ave/correlate"_fix_ave_correlate.html command enables direct +output to a file of time-correlated quantities, which can be global +values. The correlation matrix output of this fix can also be used as +input to other output commands. + +The "fix print"_fix_print.html command can generate a line of output +written to the screen and log file or to a separate file, periodically +during a running simulation. The line can contain one or more +"variable"_variable.html values for any style variable except the +vector or atom styles). As explained above, variables themselves can +contain references to global values generated by "thermodynamic +keywords"_thermo_style.html, "computes"_compute.html, +"fixes"_fix.html, or other "variables"_variable.html, or to per-atom +values for a specific atom. Thus the "fix print"_fix_print.html +command is a means to output a wide variety of quantities separate +from normal thermodynamic or dump file output. + +Computes that process output quantities :h4,link(computeoutput) + +The "compute reduce"_compute_reduce.html and "compute +reduce/region"_compute_reduce.html commands take one or more per-atom +or local vector quantities as inputs and "reduce" them (sum, min, max, +ave) to scalar quantities. These are produced as output values which +can be used as input to other output commands. + +The "compute slice"_compute_slice.html command take one or more global +vector or array quantities as inputs and extracts a subset of their +values to create a new vector or array. These are produced as output +values which can be used as input to other output commands. + +The "compute property/atom"_compute_property_atom.html command takes a +list of one or more pre-defined atom attributes (id, x, fx, etc) and +stores the values in a per-atom vector or array. These are produced +as output values which can be used as input to other output commands. +The list of atom attributes is the same as for the "dump +custom"_dump.html command. + +The "compute property/local"_compute_property_local.html command takes +a list of one or more pre-defined local attributes (bond info, angle +info, etc) and stores the values in a local vector or array. These +are produced as output values which can be used as input to other +output commands. + +Fixes that process output quantities :h4,link(fixprocoutput) + +The "fix vector"_fix_vector.html command can create global vectors as +output from global scalars as input, accumulating them one element at +a time. + +The "fix ave/atom"_fix_ave_atom.html command performs time-averaging +of per-atom vectors. The per-atom quantities can be atom attributes +such as position, velocity, force. They can also be per-atom +quantities calculated by a "compute"_compute.html, by a +"fix"_fix.html, or by an atom-style "variable"_variable.html. The +time-averaged per-atom output of this fix can be used as input to +other output commands. + +The "fix store/state"_fix_store_state.html command can archive one or +more per-atom attributes at a particular time, so that the old values +can be used in a future calculation or output. The list of atom +attributes is the same as for the "dump custom"_dump.html command, +including per-atom quantities calculated by a "compute"_compute.html, +by a "fix"_fix.html, or by an atom-style "variable"_variable.html. +The output of this fix can be used as input to other output commands. + +Computes that generate values to output :h4,link(compute) + +Every "compute"_compute.html in LAMMPS produces either global or +per-atom or local values. The values can be scalars or vectors or +arrays of data. These values can be output using the other commands +described in this section. The doc page for each compute command +describes what it produces. Computes that produce per-atom or local +values have the word "atom" or "local" in their style name. Computes +without the word "atom" or "local" produce global values. + +Fixes that generate values to output :h4,link(fix) + +Some "fixes"_fix.html in LAMMPS produces either global or per-atom or +local values which can be accessed by other commands. The values can +be scalars or vectors or arrays of data. These values can be output +using the other commands described in this section. The doc page for +each fix command tells whether it produces any output quantities and +describes them. + +Variables that generate values to output :h4,link(variable) + +"Variables"_variable.html defined in an input script can store one or +more strings. But equal-style, vector-style, and atom-style or +atomfile-style variables generate a global scalar value, global vector +or values, or a per-atom vector, respectively, when accessed. The +formulas used to define these variables can contain references to the +thermodynamic keywords and to global and per-atom data generated by +computes, fixes, and other variables. The values generated by +variables can be used as input to and thus output by the other +commands described in this section. + +Summary table of output options and data flow between commands :h4,link(table) + +This table summarizes the various commands that can be used for +generating output from LAMMPS. Each command produces output data of +some kind and/or writes data to a file. Most of the commands can take +data from other commands as input. Thus you can link many of these +commands together in pipeline form, where data produced by one command +is used as input to another command and eventually written to the +screen or to a file. Note that to hook two commands together the +output and input data types must match, e.g. global/per-atom/local +data and scalar/vector/array data. + +Also note that, as described above, when a command takes a scalar as +input, that could be an element of a vector or array. Likewise a +vector input could be a column of an array. + +Command: Input: Output: +"thermo_style custom"_thermo_style.html: global scalars: screen, log file: +"dump custom"_dump.html: per-atom vectors: dump file: +"dump local"_dump.html: local vectors: dump file: +"fix print"_fix_print.html: global scalar from variable: screen, file: +"print"_print.html: global scalar from variable: screen: +"computes"_compute.html: N/A: global/per-atom/local scalar/vector/array: +"fixes"_fix.html: N/A: global/per-atom/local scalar/vector/array: +"variables"_variable.html: global scalars and vectors, per-atom vectors: global scalar and vector, per-atom vector: +"compute reduce"_compute_reduce.html: per-atom/local vectors: global scalar/vector: +"compute slice"_compute_slice.html: global vectors/arrays: global vector/array: +"compute property/atom"_compute_property_atom.html: per-atom vectors: per-atom vector/array: +"compute property/local"_compute_property_local.html: local vectors: local vector/array: +"fix vector"_fix_vector.html: global scalars: global vector: +"fix ave/atom"_fix_ave_atom.html: per-atom vectors: per-atom vector/array: +"fix ave/time"_fix_ave_time.html: global scalars/vectors: global scalar/vector/array, file: +"fix ave/chunk"_fix_ave_chunk.html: per-atom vectors: global array, file: +"fix ave/histo"_fix_ave_histo.html: global/per-atom/local scalars and vectors: global array, file: +"fix ave/correlate"_fix_ave_correlate.html: global scalars: global array, file: +"fix store/state"_fix_store_state.html: per-atom vectors: per-atom vector/array :tb(c=3,s=:) diff --git a/doc/src/Howto_polarizable.txt b/doc/src/Howto_polarizable.txt new file mode 100644 index 0000000000..ec96ddc9a9 --- /dev/null +++ b/doc/src/Howto_polarizable.txt @@ -0,0 +1,81 @@ +"Higher level section"_Howto.html - "LAMMPS WWW Site"_lws - "LAMMPS +Documentation"_ld - "LAMMPS Commands"_lc :c + +:link(lws,http://lammps.sandia.gov) +:link(ld,Manual.html) +:link(lc,Section_commands.html#comm) + +:line + +Polarizable models :h3 + +In polarizable force fields the charge distributions in molecules and +materials respond to their electrostatic environments. Polarizable +systems can be simulated in LAMMPS using three methods: + +the fluctuating charge method, implemented in the "QEQ"_fix_qeq.html +package, :ulb,l +the adiabatic core-shell method, implemented in the +"CORESHELL"_Howto_coreshell.html package, :l +the thermalized Drude dipole method, implemented in the +"USER-DRUDE"_Howto_drude.html package. :l,ule + +The fluctuating charge method calculates instantaneous charges on +interacting atoms based on the electronegativity equalization +principle. It is implemented in the "fix qeq"_fix_qeq.html which is +available in several variants. It is a relatively efficient technique +since no additional particles are introduced. This method allows for +charge transfer between molecules or atom groups. However, because the +charges are located at the interaction sites, off-plane components of +polarization cannot be represented in planar molecules or atom groups. + +The two other methods share the same basic idea: polarizable atoms are +split into one core atom and one satellite particle (called shell or +Drude particle) attached to it by a harmonic spring. Both atoms bear +a charge and they represent collectively an induced electric dipole. +These techniques are computationally more expensive than the QEq +method because of additional particles and bonds. These two +charge-on-spring methods differ in certain features, with the +core-shell model being normally used for ionic/crystalline materials, +whereas the so-called Drude model is normally used for molecular +systems and fluid states. + +The core-shell model is applicable to crystalline materials where the +high symmetry around each site leads to stable trajectories of the +core-shell pairs. However, bonded atoms in molecules can be so close +that a core would interact too strongly or even capture the Drude +particle of a neighbor. The Drude dipole model is relatively more +complex in order to remediate this and other issues. Specifically, the +Drude model includes specific thermostating of the core-Drude pairs +and short-range damping of the induced dipoles. + +The three polarization methods can be implemented through a +self-consistent calculation of charges or induced dipoles at each +timestep. In the fluctuating charge scheme this is done by the matrix +inversion method in "fix qeq/point"_fix_qeq.html, but for core-shell +or Drude-dipoles the relaxed-dipoles technique would require an slow +iterative procedure. These self-consistent solutions yield accurate +trajectories since the additional degrees of freedom representing +polarization are massless. An alternative is to attribute a mass to +the additional degrees of freedom and perform time integration using +an extended Lagrangian technique. For the fluctuating charge scheme +this is done by "fix qeq/dynamic"_fix_qeq.html, and for the +charge-on-spring models by the methods outlined in the next two +sections. The assignment of masses to the additional degrees of +freedom can lead to unphysical trajectories if care is not exerted in +choosing the parameters of the polarizable models and the simulation +conditions. + +In the core-shell model the vibration of the shells is kept faster +than the ionic vibrations to mimic the fast response of the +polarizable electrons. But in molecular systems thermalizing the +core-Drude pairs at temperatures comparable to the rest of the +simulation leads to several problems (kinetic energy transfer, too +short a timestep, etc.) In order to avoid these problems the relative +motion of the Drude particles with respect to their cores is kept +"cold" so the vibration of the core-Drude pairs is very slow, +approaching the self-consistent regime. In both models the +temperature is regulated using the velocities of the center of mass of +core+shell (or Drude) pairs, but in the Drude model the actual +relative core-Drude particle motion is thermostated separately as +well. diff --git a/doc/src/tutorial_pylammps.txt b/doc/src/Howto_pylammps.txt similarity index 95% rename from doc/src/tutorial_pylammps.txt rename to doc/src/Howto_pylammps.txt index 11cddb3cbf..abf7c52d05 100644 --- a/doc/src/tutorial_pylammps.txt +++ b/doc/src/Howto_pylammps.txt @@ -15,13 +15,19 @@ END_RST --> Overview :h4 -PyLammps is a Python wrapper class which can be created on its own or use an -existing lammps Python object. It creates a simpler, Python-like interface to -common LAMMPS functionality. Unlike the original flat C-types interface, it -exposes a discoverable API. It no longer requires knowledge of the underlying -C++ code implementation. Finally, the IPyLammps wrapper builds on top of -PyLammps and adds some additional features for IPython integration into IPython -notebooks, e.g. for embedded visualization output from dump/image. +PyLammps is a Python wrapper class which can be created on its own or +use an existing lammps Python object. It creates a simpler, +Python-like interface to common LAMMPS functionality, in contrast to +the lammps.py wrapper on the C-style LAMMPS library interface which is +written using Python ctypes. The lammps.py wrapper is discussed on +the "Python library"_Python_library.html doc page. + +Unlike the flat ctypes interface, PyLammps exposes a discoverable API. +It no longer requires knowledge of the underlying C++ code +implementation. Finally, the IPyLammps wrapper builds on top of +PyLammps and adds some additional features for IPython integration +into IPython notebooks, e.g. for embedded visualization output from +dump/image. Comparison of lammps and PyLammps interfaces :h5 @@ -40,7 +46,6 @@ communication with LAMMPS is hidden from API user shorter, more concise Python better IPython integration, designed for quick prototyping :ul - Quick Start :h4 System-wide Installation :h5 diff --git a/doc/src/Howto_replica.txt b/doc/src/Howto_replica.txt new file mode 100644 index 0000000000..b2f0faa209 --- /dev/null +++ b/doc/src/Howto_replica.txt @@ -0,0 +1,61 @@ +"Higher level section"_Howto.html - "LAMMPS WWW Site"_lws - "LAMMPS +Documentation"_ld - "LAMMPS Commands"_lc :c + +:link(lws,http://lammps.sandia.gov) +:link(ld,Manual.html) +:link(lc,Section_commands.html#comm) + +:line + +Multi-replica simulations :h3 + +Several commands in LAMMPS run mutli-replica simulations, meaning +that multiple instances (replicas) of your simulation are run +simultaneously, with small amounts of data exchanged between replicas +periodically. + +These are the relevant commands: + +"neb"_neb.html for nudged elastic band calculations +"prd"_prd.html for parallel replica dynamics +"tad"_tad.html for temperature accelerated dynamics +"temper"_temper.html for parallel tempering +"fix pimd"_fix_pimd.html for path-integral molecular dynamics (PIMD) :ul + +NEB is a method for finding transition states and barrier energies. +PRD and TAD are methods for performing accelerated dynamics to find +and perform infrequent events. Parallel tempering or replica exchange +runs different replicas at a series of temperature to facilitate +rare-event sampling. + +These commands can only be used if LAMMPS was built with the REPLICA +package. See the "Making LAMMPS"_Section_start.html#start_3 section +for more info on packages. + +PIMD runs different replicas whose individual particles are coupled +together by springs to model a system or ring-polymers. + +This commands can only be used if LAMMPS was built with the USER-MISC +package. See the "Making LAMMPS"_Section_start.html#start_3 section +for more info on packages. + +In all these cases, you must run with one or more processors per +replica. The processors assigned to each replica are determined at +run-time by using the "-partition command-line +switch"_Section_start.html#start_6 to launch LAMMPS on multiple +partitions, which in this context are the same as replicas. E.g. +these commands: + +mpirun -np 16 lmp_linux -partition 8x2 -in in.temper +mpirun -np 8 lmp_linux -partition 8x1 -in in.neb :pre + +would each run 8 replicas, on either 16 or 8 processors. Note the use +of the "-in command-line switch"_Section_start.html#start_6 to specify +the input script which is required when running in multi-replica mode. + +Also note that with MPI installed on a machine (e.g. your desktop), +you can run on more (virtual) processors than you have physical +processors. Thus the above commands could be run on a +single-processor (or few-processor) desktop so that you can run +a multi-replica simulation on more replicas than you have +physical processors. diff --git a/doc/src/Howto_restart.txt b/doc/src/Howto_restart.txt new file mode 100644 index 0000000000..d2a993fcd3 --- /dev/null +++ b/doc/src/Howto_restart.txt @@ -0,0 +1,97 @@ +"Higher level section"_Howto.html - "LAMMPS WWW Site"_lws - "LAMMPS +Documentation"_ld - "LAMMPS Commands"_lc :c + +:link(lws,http://lammps.sandia.gov) +:link(ld,Manual.html) +:link(lc,Section_commands.html#comm) + +:line + +Restart a simulation :h3 + +There are 3 ways to continue a long LAMMPS simulation. Multiple +"run"_run.html commands can be used in the same input script. Each +run will continue from where the previous run left off. Or binary +restart files can be saved to disk using the "restart"_restart.html +command. At a later time, these binary files can be read via a +"read_restart"_read_restart.html command in a new script. Or they can +be converted to text data files using the "-r command-line +switch"_Section_start.html#start_6 and read by a +"read_data"_read_data.html command in a new script. + +Here we give examples of 2 scripts that read either a binary restart +file or a converted data file and then issue a new run command to +continue where the previous run left off. They illustrate what +settings must be made in the new script. Details are discussed in the +documentation for the "read_restart"_read_restart.html and +"read_data"_read_data.html commands. + +Look at the {in.chain} input script provided in the {bench} directory +of the LAMMPS distribution to see the original script that these 2 +scripts are based on. If that script had the line + +restart 50 tmp.restart :pre + +added to it, it would produce 2 binary restart files (tmp.restart.50 +and tmp.restart.100) as it ran. + +This script could be used to read the 1st restart file and re-run the +last 50 timesteps: + +read_restart tmp.restart.50 :pre + +neighbor 0.4 bin +neigh_modify every 1 delay 1 :pre + +fix 1 all nve +fix 2 all langevin 1.0 1.0 10.0 904297 :pre + +timestep 0.012 :pre + +run 50 :pre + +Note that the following commands do not need to be repeated because +their settings are included in the restart file: {units, atom_style, +special_bonds, pair_style, bond_style}. However these commands do +need to be used, since their settings are not in the restart file: +{neighbor, fix, timestep}. + +If you actually use this script to perform a restarted run, you will +notice that the thermodynamic data match at step 50 (if you also put a +"thermo 50" command in the original script), but do not match at step +100. This is because the "fix langevin"_fix_langevin.html command +uses random numbers in a way that does not allow for perfect restarts. + +As an alternate approach, the restart file could be converted to a data +file as follows: + +lmp_g++ -r tmp.restart.50 tmp.restart.data :pre + +Then, this script could be used to re-run the last 50 steps: + +units lj +atom_style bond +pair_style lj/cut 1.12 +pair_modify shift yes +bond_style fene +special_bonds 0.0 1.0 1.0 :pre + +read_data tmp.restart.data :pre + +neighbor 0.4 bin +neigh_modify every 1 delay 1 :pre + +fix 1 all nve +fix 2 all langevin 1.0 1.0 10.0 904297 :pre + +timestep 0.012 :pre + +reset_timestep 50 +run 50 :pre + +Note that nearly all the settings specified in the original {in.chain} +script must be repeated, except the {pair_coeff} and {bond_coeff} +commands since the new data file lists the force field coefficients. +Also, the "reset_timestep"_reset_timestep.html command is used to tell +LAMMPS the current timestep. This value is stored in restart files, +but not in data files. diff --git a/doc/src/Howto_spc.txt b/doc/src/Howto_spc.txt new file mode 100644 index 0000000000..6a63c1f6a6 --- /dev/null +++ b/doc/src/Howto_spc.txt @@ -0,0 +1,54 @@ +"Higher level section"_Howto.html - "LAMMPS WWW Site"_lws - "LAMMPS +Documentation"_ld - "LAMMPS Commands"_lc :c + +:link(lws,http://lammps.sandia.gov) +:link(ld,Manual.html) +:link(lc,Section_commands.html#comm) + +:line + +SPC water model :h3 + +The SPC water model specifies a 3-site rigid water molecule with +charges and Lennard-Jones parameters assigned to each of the 3 atoms. +In LAMMPS the "fix shake"_fix_shake.html command can be used to hold +the two O-H bonds and the H-O-H angle rigid. A bond style of +{harmonic} and an angle style of {harmonic} or {charmm} should also be +used. + +These are the additional parameters (in real units) to set for O and H +atoms and the water molecule to run a rigid SPC model. + +O mass = 15.9994 +H mass = 1.008 +O charge = -0.820 +H charge = 0.410 +LJ epsilon of OO = 0.1553 +LJ sigma of OO = 3.166 +LJ epsilon, sigma of OH, HH = 0.0 +r0 of OH bond = 1.0 +theta of HOH angle = 109.47 :all(b),p + +Note that as originally proposed, the SPC model was run with a 9 +Angstrom cutoff for both LJ and Coulommbic terms. It can also be used +with long-range Coulombics (Ewald or PPPM in LAMMPS), without changing +any of the parameters above, though it becomes a different model in +that mode of usage. + +The SPC/E (extended) water model is the same, except +the partial charge assignments change: + +O charge = -0.8476 +H charge = 0.4238 :all(b),p + +See the "(Berendsen)"_#howto-Berendsen reference for more details on both +the SPC and SPC/E models. + +Wikipedia also has a nice article on "water +models"_http://en.wikipedia.org/wiki/Water_model. + +:line + +:link(howto-Berendsen) +[(Berendsen)] Berendsen, Grigera, Straatsma, J Phys Chem, 91, +6269-6271 (1987). diff --git a/doc/src/Howto_spherical.txt b/doc/src/Howto_spherical.txt new file mode 100644 index 0000000000..bc16ece2a3 --- /dev/null +++ b/doc/src/Howto_spherical.txt @@ -0,0 +1,243 @@ +"Higher level section"_Howto.html - "LAMMPS WWW Site"_lws - "LAMMPS +Documentation"_ld - "LAMMPS Commands"_lc :c + +:link(lws,http://lammps.sandia.gov) +:link(ld,Manual.html) +:link(lc,Section_commands.html#comm) + +:line + +Finite-size spherical and aspherical particles :h3 + +Typical MD models treat atoms or particles as point masses. Sometimes +it is desirable to have a model with finite-size particles such as +spheroids or ellipsoids or generalized aspherical bodies. The +difference is that such particles have a moment of inertia, rotational +energy, and angular momentum. Rotation is induced by torque coming +from interactions with other particles. + +LAMMPS has several options for running simulations with these kinds of +particles. The following aspects are discussed in turn: + +atom styles +pair potentials +time integration +computes, thermodynamics, and dump output +rigid bodies composed of finite-size particles :ul + +Example input scripts for these kinds of models are in the body, +colloid, dipole, ellipse, line, peri, pour, and tri directories of the +"examples directory"_Examples.html in the LAMMPS distribution. + +Atom styles :h4 + +There are several "atom styles"_atom_style.html that allow for +definition of finite-size particles: sphere, dipole, ellipsoid, line, +tri, peri, and body. + +The sphere style defines particles that are spheriods and each +particle can have a unique diameter and mass (or density). These +particles store an angular velocity (omega) and can be acted upon by +torque. The "set" command can be used to modify the diameter and mass +of individual particles, after then are created. + +The dipole style does not actually define finite-size particles, but +is often used in conjunction with spherical particles, via a command +like + +atom_style hybrid sphere dipole :pre + +This is because when dipoles interact with each other, they induce +torques, and a particle must be finite-size (i.e. have a moment of +inertia) in order to respond and rotate. See the "atom_style +dipole"_atom_style.html command for details. The "set" command can be +used to modify the orientation and length of the dipole moment of +individual particles, after then are created. + +The ellipsoid style defines particles that are ellipsoids and thus can +be aspherical. Each particle has a shape, specified by 3 diameters, +and mass (or density). These particles store an angular momentum and +their orientation (quaternion), and can be acted upon by torque. They +do not store an angular velocity (omega), which can be in a different +direction than angular momentum, rather they compute it as needed. +The "set" command can be used to modify the diameter, orientation, and +mass of individual particles, after then are created. It also has a +brief explanation of what quaternions are. + +The line style defines line segment particles with two end points and +a mass (or density). They can be used in 2d simulations, and they can +be joined together to form rigid bodies which represent arbitrary +polygons. + +The tri style defines triangular particles with three corner points +and a mass (or density). They can be used in 3d simulations, and they +can be joined together to form rigid bodies which represent arbitrary +particles with a triangulated surface. + +The peri style is used with "Peridynamic models"_pair_peri.html and +defines particles as having a volume, that is used internally in the +"pair_style peri"_pair_peri.html potentials. + +The body style allows for definition of particles which can represent +complex entities, such as surface meshes of discrete points, +collections of sub-particles, deformable objects, etc. The body style +is discussed in more detail on the "Howto body"_Howto_body.html doc +page. + +Note that if one of these atom styles is used (or multiple styles via +the "atom_style hybrid"_atom_style.html command), not all particles in +the system are required to be finite-size or aspherical. + +For example, in the ellipsoid style, if the 3 shape parameters are set +to the same value, the particle will be a sphere rather than an +ellipsoid. If the 3 shape parameters are all set to 0.0 or if the +diameter is set to 0.0, it will be a point particle. In the line or +tri style, if the lineflag or triflag is specified as 0, then it +will be a point particle. + +Some of the pair styles used to compute pairwise interactions between +finite-size particles also compute the correct interaction with point +particles as well, e.g. the interaction between a point particle and a +finite-size particle or between two point particles. If necessary, +"pair_style hybrid"_pair_hybrid.html can be used to insure the correct +interactions are computed for the appropriate style of interactions. +Likewise, using groups to partition particles (ellipsoids versus +spheres versus point particles) will allow you to use the appropriate +time integrators and temperature computations for each class of +particles. See the doc pages for various commands for details. + +Also note that for "2d simulations"_dimension.html, atom styles sphere +and ellipsoid still use 3d particles, rather than as circular disks or +ellipses. This means they have the same moment of inertia as the 3d +object. When temperature is computed, the correct degrees of freedom +are used for rotation in a 2d versus 3d system. + +Pair potentials :h4 + +When a system with finite-size particles is defined, the particles +will only rotate and experience torque if the force field computes +such interactions. These are the various "pair +styles"_pair_style.html that generate torque: + +"pair_style gran/history"_pair_gran.html +"pair_style gran/hertzian"_pair_gran.html +"pair_style gran/no_history"_pair_gran.html +"pair_style dipole/cut"_pair_dipole.html +"pair_style gayberne"_pair_gayberne.html +"pair_style resquared"_pair_resquared.html +"pair_style brownian"_pair_brownian.html +"pair_style lubricate"_pair_lubricate.html +"pair_style line/lj"_pair_line_lj.html +"pair_style tri/lj"_pair_tri_lj.html +"pair_style body"_pair_body.html :ul + +The granular pair styles are used with spherical particles. The +dipole pair style is used with the dipole atom style, which could be +applied to spherical or ellipsoidal particles. The GayBerne and +REsquared potentials require ellipsoidal particles, though they will +also work if the 3 shape parameters are the same (a sphere). The +Brownian and lubrication potentials are used with spherical particles. +The line, tri, and body potentials are used with line segment, +triangular, and body particles respectively. + +Time integration :h4 + +There are several fixes that perform time integration on finite-size +spherical particles, meaning the integrators update the rotational +orientation and angular velocity or angular momentum of the particles: + +"fix nve/sphere"_fix_nve_sphere.html +"fix nvt/sphere"_fix_nvt_sphere.html +"fix npt/sphere"_fix_npt_sphere.html :ul + +Likewise, there are 3 fixes that perform time integration on +ellipsoidal particles: + +"fix nve/asphere"_fix_nve_asphere.html +"fix nvt/asphere"_fix_nvt_asphere.html +"fix npt/asphere"_fix_npt_asphere.html :ul + +The advantage of these fixes is that those which thermostat the +particles include the rotational degrees of freedom in the temperature +calculation and thermostatting. The "fix langevin"_fix_langevin +command can also be used with its {omgea} or {angmom} options to +thermostat the rotational degrees of freedom for spherical or +ellipsoidal particles. Other thermostatting fixes only operate on the +translational kinetic energy of finite-size particles. + +These fixes perform constant NVE time integration on line segment, +triangular, and body particles: + +"fix nve/line"_fix_nve_line.html +"fix nve/tri"_fix_nve_tri.html +"fix nve/body"_fix_nve_body.html :ul + +Note that for mixtures of point and finite-size particles, these +integration fixes can only be used with "groups"_group.html which +contain finite-size particles. + +Computes, thermodynamics, and dump output :h4 + +There are several computes that calculate the temperature or +rotational energy of spherical or ellipsoidal particles: + +"compute temp/sphere"_compute_temp_sphere.html +"compute temp/asphere"_compute_temp_asphere.html +"compute erotate/sphere"_compute_erotate_sphere.html +"compute erotate/asphere"_compute_erotate_asphere.html :ul + +These include rotational degrees of freedom in their computation. If +you wish the thermodynamic output of temperature or pressure to use +one of these computes (e.g. for a system entirely composed of +finite-size particles), then the compute can be defined and the +"thermo_modify"_thermo_modify.html command used. Note that by default +thermodynamic quantities will be calculated with a temperature that +only includes translational degrees of freedom. See the +"thermo_style"_thermo_style.html command for details. + +These commands can be used to output various attributes of finite-size +particles: + +"dump custom"_dump.html +"compute property/atom"_compute_property_atom.html +"dump local"_dump.html +"compute body/local"_compute_body_local.html :ul + +Attributes include the dipole moment, the angular velocity, the +angular momentum, the quaternion, the torque, the end-point and +corner-point coordinates (for line and tri particles), and +sub-particle attributes of body particles. + +Rigid bodies composed of finite-size particles :h4 + +The "fix rigid"_fix_rigid.html command treats a collection of +particles as a rigid body, computes its inertia tensor, sums the total +force and torque on the rigid body each timestep due to forces on its +constituent particles, and integrates the motion of the rigid body. + +If any of the constituent particles of a rigid body are finite-size +particles (spheres or ellipsoids or line segments or triangles), then +their contribution to the inertia tensor of the body is different than +if they were point particles. This means the rotational dynamics of +the rigid body will be different. Thus a model of a dimer is +different if the dimer consists of two point masses versus two +spheroids, even if the two particles have the same mass. Finite-size +particles that experience torque due to their interaction with other +particles will also impart that torque to a rigid body they are part +of. + +See the "fix rigid" command for example of complex rigid-body models +it is possible to define in LAMMPS. + +Note that the "fix shake"_fix_shake.html command can also be used to +treat 2, 3, or 4 particles as a rigid body, but it always assumes the +particles are point masses. + +Also note that body particles cannot be modeled with the "fix +rigid"_fix_rigid.html command. Body particles are treated by LAMMPS +as single particles, though they can store internal state, such as a +list of sub-particles. Individual body partices are typically treated +as rigid bodies, and their motion integrated with a command like "fix +nve/body"_fix_nve_body.html. Interactions between pairs of body +particles are computed via a command like "pair_style +body"_pair_body.html. diff --git a/doc/src/Howto_spins.txt b/doc/src/Howto_spins.txt new file mode 100644 index 0000000000..3cb9e480b2 --- /dev/null +++ b/doc/src/Howto_spins.txt @@ -0,0 +1,59 @@ +"Higher level section"_Howto.html - "LAMMPS WWW Site"_lws - "LAMMPS +Documentation"_ld - "LAMMPS Commands"_lc :c + +:link(lws,http://lammps.sandia.gov) +:link(ld,Manual.html) +:link(lc,Section_commands.html#comm) + +:line + +Magnetic spins :h3 + +The magnetic spin simualtions are enabled by the SPIN package, whose +implementation is detailed in "Tranchida"_#Tranchida7. + +The model representents the simulation of atomic magnetic spins coupled +to lattice vibrations. The dynamics of those magnetic spins can be used +to simulate a broad range a phenomena related to magneto-elasticity, or +or to study the influence of defects on the magnetic properties of +materials. + +The magnetic spins are interacting with each others and with the +lattice via pair interactions. Typically, the magnetic exchange +interaction can be defined using the +"pair/spin/exchange"_pair_spin_exchange.html command. This exchange +applies a magnetic torque to a given spin, considering the orientation +of its neighboring spins and their relative distances. +It also applies a force on the atoms as a function of the spin +orientations and their associated inter-atomic distances. + +The command "fix precession/spin"_fix_precession_spin.html allows to +apply a constant magnetic torque on all the spins in the system. This +torque can be an external magnetic field (Zeeman interaction), or an +uniaxial magnetic anisotropy. + +A Langevin thermostat can be applied to those magnetic spins using +"fix langevin/spin"_fix_langevin_spin.html. Typically, this thermostat +can be coupled to another Langevin thermostat applied to the atoms +using "fix langevin"_fix_langevin.html in order to simulate +thermostated spin-lattice system. + +The magnetic Gilbert damping can also be applied using "fix +langevin/spin"_fix_langevin_spin.html. It allows to either dissipate +the thermal energy of the Langevin thermostat, or to perform a +relaxation of the magnetic configuration toward an equilibrium state. + +All the computed magnetic properties can be outputed by two main +commands. The first one is "compute spin"_compute_spin.html, that +enables to evaluate magnetic averaged quantities, such as the total +magnetization of the system along x, y, or z, the spin temperature, or +the magnetic energy. The second command is "compute +property/atom"_compute_property_atom.html. It enables to output all the +per atom magnetic quantities. Typically, the orientation of a given +magnetic spin, or the magnetic force acting on this spin. + +:line + +:link(Tranchida7) +[(Tranchida)] Tranchida, Plimpton, Thibaudeau and Thompson, +arXiv preprint arXiv:1801.10233, (2018). diff --git a/doc/src/Howto_temperature.txt b/doc/src/Howto_temperature.txt new file mode 100644 index 0000000000..3d1bd8a2d6 --- /dev/null +++ b/doc/src/Howto_temperature.txt @@ -0,0 +1,40 @@ +"Higher level section"_Howto.html - "LAMMPS WWW Site"_lws - "LAMMPS +Documentation"_ld - "LAMMPS Commands"_lc :c + +:link(lws,http://lammps.sandia.gov) +:link(ld,Manual.html) +:link(lc,Section_commands.html#comm) + +:line + +Calcalate temperature :h3 + +Temperature is computed as kinetic energy divided by some number of +degrees of freedom (and the Boltzmann constant). Since kinetic energy +is a function of particle velocity, there is often a need to +distinguish between a particle's advection velocity (due to some +aggregate motion of particles) and its thermal velocity. The sum of +the two is the particle's total velocity, but the latter is often what +is wanted to compute a temperature. + +LAMMPS has several options for computing temperatures, any of which can be used in "thermostatting"_Howto_thermostat.html and "barostatting"_Howto_barostat.html. These "compute commands"_compute.html calculate temperature: + +"compute temp"_compute_temp.html +"compute temp/sphere"_compute_temp_sphere.html +"compute temp/asphere"_compute_temp_asphere.html +"compute temp/com"_compute_temp_com.html +"compute temp/deform"_compute_temp_deform.html +"compute temp/partial"_compute_temp_partial.html +"compute temp/profile"_compute_temp_profile.html +"compute temp/ramp"_compute_temp_ramp.html +"compute temp/region"_compute_temp_region.html :ul + +All but the first 3 calculate velocity biases directly (e.g. advection +velocities) that are removed when computing the thermal temperature. +"Compute temp/sphere"_compute_temp_sphere.html and "compute +temp/asphere"_compute_temp_asphere.html compute kinetic energy for +finite-size particles that includes rotational degrees of freedom. +They both allow for velocity biases indirectly, via an optional extra +argument which is another temperature compute that subtracts a velocity bias. +This allows the translational velocity of spherical or aspherical +particles to be adjusted in prescribed ways. diff --git a/doc/src/Howto_thermostat.txt b/doc/src/Howto_thermostat.txt new file mode 100644 index 0000000000..c1887d9738 --- /dev/null +++ b/doc/src/Howto_thermostat.txt @@ -0,0 +1,89 @@ +"Higher level section"_Howto.html - "LAMMPS WWW Site"_lws - "LAMMPS +Documentation"_ld - "LAMMPS Commands"_lc :c + +:link(lws,http://lammps.sandia.gov) +:link(ld,Manual.html) +:link(lc,Section_commands.html#comm) + +:line + +Thermostats :h3 + +Thermostatting means controlling the temperature of particles in an MD +simulation. "Barostatting"_Howto_barostat.html means controlling the +pressure. Since the pressure includes a kinetic component due to +particle velocities, both these operations require calculation of the +temperature. Typically a target temperature (T) and/or pressure (P) +is specified by the user, and the thermostat or barostat attempts to +equilibrate the system to the requested T and/or P. + +Thermostatting in LAMMPS is performed by "fixes"_fix.html, or in one +case by a pair style. Several thermostatting fixes are available: +Nose-Hoover (nvt), Berendsen, CSVR, Langevin, and direct rescaling +(temp/rescale). Dissipative particle dynamics (DPD) thermostatting +can be invoked via the {dpd/tstat} pair style: + +"fix nvt"_fix_nh.html +"fix nvt/sphere"_fix_nvt_sphere.html +"fix nvt/asphere"_fix_nvt_asphere.html +"fix nvt/sllod"_fix_nvt_sllod.html +"fix temp/berendsen"_fix_temp_berendsen.html +"fix temp/csvr"_fix_temp_csvr.html +"fix langevin"_fix_langevin.html +"fix temp/rescale"_fix_temp_rescale.html +"pair_style dpd/tstat"_pair_dpd.html :ul + +"Fix nvt"_fix_nh.html only thermostats the translational velocity of +particles. "Fix nvt/sllod"_fix_nvt_sllod.html also does this, except +that it subtracts out a velocity bias due to a deforming box and +integrates the SLLOD equations of motion. See the "Howto +nemd"_Howto_nemd.html doc page for further details. "Fix +nvt/sphere"_fix_nvt_sphere.html and "fix +nvt/asphere"_fix_nvt_asphere.html thermostat not only translation +velocities but also rotational velocities for spherical and aspherical +particles. + +DPD thermostatting alters pairwise interactions in a manner analogous +to the per-particle thermostatting of "fix +langevin"_fix_langevin.html. + +Any of the thermostatting fixes can use "temperature +computes"_Howto_thermostat.html that remove bias which has two +effects. First, the current calculated temperature, which is compared +to the requested target temperature, is calculated with the velocity +bias removed. Second, the thermostat adjusts only the thermal +temperature component of the particle's velocities, which are the +velocities with the bias removed. The removed bias is then added back +to the adjusted velocities. See the doc pages for the individual +fixes and for the "fix_modify"_fix_modify.html command for +instructions on how to assign a temperature compute to a +thermostatting fix. For example, you can apply a thermostat to only +the x and z components of velocity by using it in conjunction with +"compute temp/partial"_compute_temp_partial.html. Of you could +thermostat only the thermal temperature of a streaming flow of +particles without affecting the streaming velocity, by using "compute +temp/profile"_compute_temp_profile.html. + +NOTE: Only the nvt fixes perform time integration, meaning they update +the velocities and positions of particles due to forces and velocities +respectively. The other thermostat fixes only adjust velocities; they +do NOT perform time integration updates. Thus they should be used in +conjunction with a constant NVE integration fix such as these: + +"fix nve"_fix_nve.html +"fix nve/sphere"_fix_nve_sphere.html +"fix nve/asphere"_fix_nve_asphere.html :ul + +Thermodynamic output, which can be setup via the +"thermo_style"_thermo_style.html command, often includes temperature +values. As explained on the doc page for the +"thermo_style"_thermo_style.html command, the default temperature is +setup by the thermo command itself. It is NOT the temperature +associated with any thermostatting fix you have defined or with any +compute you have defined that calculates a temperature. The doc pages +for the thermostatting fixes explain the ID of the temperature compute +they create. Thus if you want to view these temperatures, you need to +specify them explicitly via the "thermo_style +custom"_thermo_style.html command. Or you can use the +"thermo_modify"_thermo_modify.html command to re-define what +temperature compute is used for default thermodynamic output. diff --git a/doc/src/Howto_tip3p.txt b/doc/src/Howto_tip3p.txt new file mode 100644 index 0000000000..23ab604d1f --- /dev/null +++ b/doc/src/Howto_tip3p.txt @@ -0,0 +1,69 @@ +"Higher level section"_Howto.html - "LAMMPS WWW Site"_lws - "LAMMPS +Documentation"_ld - "LAMMPS Commands"_lc :c + +:link(lws,http://lammps.sandia.gov) +:link(ld,Manual.html) +:link(lc,Section_commands.html#comm) + +:line + +TIP3P water model :h3 + +The TIP3P water model as implemented in CHARMM +"(MacKerell)"_#howto-MacKerell specifies a 3-site rigid water molecule with +charges and Lennard-Jones parameters assigned to each of the 3 atoms. +In LAMMPS the "fix shake"_fix_shake.html command can be used to hold +the two O-H bonds and the H-O-H angle rigid. A bond style of +{harmonic} and an angle style of {harmonic} or {charmm} should also be +used. + +These are the additional parameters (in real units) to set for O and H +atoms and the water molecule to run a rigid TIP3P-CHARMM model with a +cutoff. The K values can be used if a flexible TIP3P model (without +fix shake) is desired. If the LJ epsilon and sigma for HH and OH are +set to 0.0, it corresponds to the original 1983 TIP3P model +"(Jorgensen)"_#Jorgensen1. + +O mass = 15.9994 +H mass = 1.008 +O charge = -0.834 +H charge = 0.417 +LJ epsilon of OO = 0.1521 +LJ sigma of OO = 3.1507 +LJ epsilon of HH = 0.0460 +LJ sigma of HH = 0.4000 +LJ epsilon of OH = 0.0836 +LJ sigma of OH = 1.7753 +K of OH bond = 450 +r0 of OH bond = 0.9572 +K of HOH angle = 55 +theta of HOH angle = 104.52 :all(b),p + +These are the parameters to use for TIP3P with a long-range Coulombic +solver (e.g. Ewald or PPPM in LAMMPS), see "(Price)"_#Price1 for +details: + +O mass = 15.9994 +H mass = 1.008 +O charge = -0.830 +H charge = 0.415 +LJ epsilon of OO = 0.102 +LJ sigma of OO = 3.188 +LJ epsilon, sigma of OH, HH = 0.0 +K of OH bond = 450 +r0 of OH bond = 0.9572 +K of HOH angle = 55 +theta of HOH angle = 104.52 :all(b),p + +Wikipedia also has a nice article on "water +models"_http://en.wikipedia.org/wiki/Water_model. + +:line + +:link(Jorgensen1) +[(Jorgensen)] Jorgensen, Chandrasekhar, Madura, Impey, Klein, J Chem +Phys, 79, 926 (1983). + +:link(Price1) +[(Price)] Price and Brooks, J Chem Phys, 121, 10096 (2004). + diff --git a/doc/src/Howto_tip4p.txt b/doc/src/Howto_tip4p.txt new file mode 100644 index 0000000000..a471bdc918 --- /dev/null +++ b/doc/src/Howto_tip4p.txt @@ -0,0 +1,112 @@ +"Higher level section"_Howto.html - "LAMMPS WWW Site"_lws - "LAMMPS +Documentation"_ld - "LAMMPS Commands"_lc :c + +:link(lws,http://lammps.sandia.gov) +:link(ld,Manual.html) +:link(lc,Section_commands.html#comm) + +:line + +TIP4P water model :h3 + +The four-point TIP4P rigid water model extends the traditional +three-point TIP3P model by adding an additional site, usually +massless, where the charge associated with the oxygen atom is placed. +This site M is located at a fixed distance away from the oxygen along +the bisector of the HOH bond angle. A bond style of {harmonic} and an +angle style of {harmonic} or {charmm} should also be used. + +A TIP4P model is run with LAMMPS using either this command +for a cutoff model: + +"pair_style lj/cut/tip4p/cut"_pair_lj.html + +or these two commands for a long-range model: + +"pair_style lj/cut/tip4p/long"_pair_lj.html +"kspace_style pppm/tip4p"_kspace_style.html :ul + +For both models, the bond lengths and bond angles should be held fixed +using the "fix shake"_fix_shake.html command. + +These are the additional parameters (in real units) to set for O and H +atoms and the water molecule to run a rigid TIP4P model with a cutoff +"(Jorgensen)"_#Jorgensen1. Note that the OM distance is specified in +the "pair_style"_pair_style.html command, not as part of the pair +coefficients. + +O mass = 15.9994 +H mass = 1.008 +O charge = -1.040 +H charge = 0.520 +r0 of OH bond = 0.9572 +theta of HOH angle = 104.52 +OM distance = 0.15 +LJ epsilon of O-O = 0.1550 +LJ sigma of O-O = 3.1536 +LJ epsilon, sigma of OH, HH = 0.0 +Coulombic cutoff = 8.5 :all(b),p + +For the TIP4/Ice model (J Chem Phys, 122, 234511 (2005); +http://dx.doi.org/10.1063/1.1931662) these values can be used: + +O mass = 15.9994 +H mass = 1.008 +O charge = -1.1794 +H charge = 0.5897 +r0 of OH bond = 0.9572 +theta of HOH angle = 104.52 +OM distance = 0.1577 +LJ epsilon of O-O = 0.21084 +LJ sigma of O-O = 3.1668 +LJ epsilon, sigma of OH, HH = 0.0 +Coulombic cutoff = 8.5 :all(b),p + +For the TIP4P/2005 model (J Chem Phys, 123, 234505 (2005); +http://dx.doi.org/10.1063/1.2121687), these values can be used: + +O mass = 15.9994 +H mass = 1.008 +O charge = -1.1128 +H charge = 0.5564 +r0 of OH bond = 0.9572 +theta of HOH angle = 104.52 +OM distance = 0.1546 +LJ epsilon of O-O = 0.1852 +LJ sigma of O-O = 3.1589 +LJ epsilon, sigma of OH, HH = 0.0 +Coulombic cutoff = 8.5 :all(b),p + +These are the parameters to use for TIP4P with a long-range Coulombic +solver (e.g. Ewald or PPPM in LAMMPS): + +O mass = 15.9994 +H mass = 1.008 +O charge = -1.0484 +H charge = 0.5242 +r0 of OH bond = 0.9572 +theta of HOH angle = 104.52 +OM distance = 0.1250 +LJ epsilon of O-O = 0.16275 +LJ sigma of O-O = 3.16435 +LJ epsilon, sigma of OH, HH = 0.0 :all(b),p + +Note that the when using the TIP4P pair style, the neighbor list +cutoff for Coulomb interactions is effectively extended by a distance +2 * (OM distance), to account for the offset distance of the +fictitious charges on O atoms in water molecules. Thus it is +typically best in an efficiency sense to use a LJ cutoff >= Coulomb +cutoff + 2*(OM distance), to shrink the size of the neighbor list. +This leads to slightly larger cost for the long-range calculation, so +you can test the trade-off for your model. The OM distance and the LJ +and Coulombic cutoffs are set in the "pair_style +lj/cut/tip4p/long"_pair_lj.html command. + +Wikipedia also has a nice article on "water +models"_http://en.wikipedia.org/wiki/Water_model. + +:line + +:link(Jorgensen1) +[(Jorgensen)] Jorgensen, Chandrasekhar, Madura, Impey, Klein, J Chem +Phys, 79, 926 (1983). diff --git a/doc/src/Howto_triclinic.txt b/doc/src/Howto_triclinic.txt new file mode 100644 index 0000000000..10bcc5e9d1 --- /dev/null +++ b/doc/src/Howto_triclinic.txt @@ -0,0 +1,213 @@ +"Higher level section"_Howto.html - "LAMMPS WWW Site"_lws - "LAMMPS +Documentation"_ld - "LAMMPS Commands"_lc :c + +:link(lws,http://lammps.sandia.gov) +:link(ld,Manual.html) +:link(lc,Section_commands.html#comm) + +Triclinic (non-orthogonal) simulation boxes :h3 + +By default, LAMMPS uses an orthogonal simulation box to encompass the +particles. The "boundary"_boundary.html command sets the boundary +conditions of the box (periodic, non-periodic, etc). The orthogonal +box has its "origin" at (xlo,ylo,zlo) and is defined by 3 edge vectors +starting from the origin given by [a] = (xhi-xlo,0,0); [b] = +(0,yhi-ylo,0); [c] = (0,0,zhi-zlo). The 6 parameters +(xlo,xhi,ylo,yhi,zlo,zhi) are defined at the time the simulation box +is created, e.g. by the "create_box"_create_box.html or +"read_data"_read_data.html or "read_restart"_read_restart.html +commands. Additionally, LAMMPS defines box size parameters lx,ly,lz +where lx = xhi-xlo, and similarly in the y and z dimensions. The 6 +parameters, as well as lx,ly,lz, can be output via the "thermo_style +custom"_thermo_style.html command. + +LAMMPS also allows simulations to be performed in triclinic +(non-orthogonal) simulation boxes shaped as a parallelepiped with +triclinic symmetry. The parallelepiped has its "origin" at +(xlo,ylo,zlo) and is defined by 3 edge vectors starting from the +origin given by [a] = (xhi-xlo,0,0); [b] = (xy,yhi-ylo,0); [c] = +(xz,yz,zhi-zlo). {xy,xz,yz} can be 0.0 or positive or negative values +and are called "tilt factors" because they are the amount of +displacement applied to faces of an originally orthogonal box to +transform it into the parallelepiped. In LAMMPS the triclinic +simulation box edge vectors [a], [b], and [c] cannot be arbitrary +vectors. As indicated, [a] must lie on the positive x axis. [b] must +lie in the xy plane, with strictly positive y component. [c] may have +any orientation with strictly positive z component. The requirement +that [a], [b], and [c] have strictly positive x, y, and z components, +respectively, ensures that [a], [b], and [c] form a complete +right-handed basis. These restrictions impose no loss of generality, +since it is possible to rotate/invert any set of 3 crystal basis +vectors so that they conform to the restrictions. + +For example, assume that the 3 vectors [A],[B],[C] are the edge +vectors of a general parallelepiped, where there is no restriction on +[A],[B],[C] other than they form a complete right-handed basis i.e. +[A] x [B] . [C] > 0. The equivalent LAMMPS [a],[b],[c] are a linear +rotation of [A], [B], and [C] and can be computed as follows: + +:c,image(Eqs/transform.jpg) + +where A = | [A] | indicates the scalar length of [A]. The hat symbol (^) +indicates the corresponding unit vector. {beta} and {gamma} are angles +between the vectors described below. Note that by construction, +[a], [b], and [c] have strictly positive x, y, and z components, respectively. +If it should happen that +[A], [B], and [C] form a left-handed basis, then the above equations +are not valid for [c]. In this case, it is necessary +to first apply an inversion. This can be achieved +by interchanging two basis vectors or by changing the sign of one of them. + +For consistency, the same rotation/inversion applied to the basis vectors +must also be applied to atom positions, velocities, +and any other vector quantities. +This can be conveniently achieved by first converting to +fractional coordinates in the +old basis and then converting to distance coordinates in the new basis. +The transformation is given by the following equation: + +:c,image(Eqs/rotate.jpg) + +where {V} is the volume of the box, [X] is the original vector quantity and +[x] is the vector in the LAMMPS basis. + +There is no requirement that a triclinic box be periodic in any +dimension, though it typically should be in at least the 2nd dimension +of the tilt (y in xy) if you want to enforce a shift in periodic +boundary conditions across that boundary. Some commands that work +with triclinic boxes, e.g. the "fix deform"_fix_deform.html and "fix +npt"_fix_nh.html commands, require periodicity or non-shrink-wrap +boundary conditions in specific dimensions. See the command doc pages +for details. + +The 9 parameters (xlo,xhi,ylo,yhi,zlo,zhi,xy,xz,yz) are defined at the +time the simulation box is created. This happens in one of 3 ways. +If the "create_box"_create_box.html command is used with a region of +style {prism}, then a triclinic box is setup. See the +"region"_region.html command for details. If the +"read_data"_read_data.html command is used to define the simulation +box, and the header of the data file contains a line with the "xy xz +yz" keyword, then a triclinic box is setup. See the +"read_data"_read_data.html command for details. Finally, if the +"read_restart"_read_restart.html command reads a restart file which +was written from a simulation using a triclinic box, then a triclinic +box will be setup for the restarted simulation. + +Note that you can define a triclinic box with all 3 tilt factors = +0.0, so that it is initially orthogonal. This is necessary if the box +will become non-orthogonal, e.g. due to the "fix npt"_fix_nh.html or +"fix deform"_fix_deform.html commands. Alternatively, you can use the +"change_box"_change_box.html command to convert a simulation box from +orthogonal to triclinic and vice versa. + +As with orthogonal boxes, LAMMPS defines triclinic box size parameters +lx,ly,lz where lx = xhi-xlo, and similarly in the y and z dimensions. +The 9 parameters, as well as lx,ly,lz, can be output via the +"thermo_style custom"_thermo_style.html command. + +To avoid extremely tilted boxes (which would be computationally +inefficient), LAMMPS normally requires that no tilt factor can skew +the box more than half the distance of the parallel box length, which +is the 1st dimension in the tilt factor (x for xz). This is required +both when the simulation box is created, e.g. via the +"create_box"_create_box.html or "read_data"_read_data.html commands, +as well as when the box shape changes dynamically during a simulation, +e.g. via the "fix deform"_fix_deform.html or "fix npt"_fix_nh.html +commands. + +For example, if xlo = 2 and xhi = 12, then the x box length is 10 and +the xy tilt factor must be between -5 and 5. Similarly, both xz and +yz must be between -(xhi-xlo)/2 and +(yhi-ylo)/2. Note that this is +not a limitation, since if the maximum tilt factor is 5 (as in this +example), then configurations with tilt = ..., -15, -5, 5, 15, 25, +... are geometrically all equivalent. If the box tilt exceeds this +limit during a dynamics run (e.g. via the "fix deform"_fix_deform.html +command), then the box is "flipped" to an equivalent shape with a tilt +factor within the bounds, so the run can continue. See the "fix +deform"_fix_deform.html doc page for further details. + +One exception to this rule is if the 1st dimension in the tilt +factor (x for xy) is non-periodic. In that case, the limits on the +tilt factor are not enforced, since flipping the box in that dimension +does not change the atom positions due to non-periodicity. In this +mode, if you tilt the system to extreme angles, the simulation will +simply become inefficient, due to the highly skewed simulation box. + +The limitation on not creating a simulation box with a tilt factor +skewing the box more than half the distance of the parallel box length +can be overridden via the "box"_box.html command. Setting the {tilt} +keyword to {large} allows any tilt factors to be specified. + +Box flips that may occur using the "fix deform"_fix_deform.html or +"fix npt"_fix_nh.html commands can be turned off using the {flip no} +option with either of the commands. + +Note that if a simulation box has a large tilt factor, LAMMPS will run +less efficiently, due to the large volume of communication needed to +acquire ghost atoms around a processor's irregular-shaped sub-domain. +For extreme values of tilt, LAMMPS may also lose atoms and generate an +error. + +Triclinic crystal structures are often defined using three lattice +constants {a}, {b}, and {c}, and three angles {alpha}, {beta} and +{gamma}. Note that in this nomenclature, the a, b, and c lattice +constants are the scalar lengths of the edge vectors [a], [b], and [c] +defined above. The relationship between these 6 quantities +(a,b,c,alpha,beta,gamma) and the LAMMPS box sizes (lx,ly,lz) = +(xhi-xlo,yhi-ylo,zhi-zlo) and tilt factors (xy,xz,yz) is as follows: + +:c,image(Eqs/box.jpg) + +The inverse relationship can be written as follows: + +:c,image(Eqs/box_inverse.jpg) + +The values of {a}, {b}, {c} , {alpha}, {beta} , and {gamma} can be printed +out or accessed by computes using the +"thermo_style custom"_thermo_style.html keywords +{cella}, {cellb}, {cellc}, {cellalpha}, {cellbeta}, {cellgamma}, +respectively. + +As discussed on the "dump"_dump.html command doc page, when the BOX +BOUNDS for a snapshot is written to a dump file for a triclinic box, +an orthogonal bounding box which encloses the triclinic simulation box +is output, along with the 3 tilt factors (xy, xz, yz) of the triclinic +box, formatted as follows: + +ITEM: BOX BOUNDS xy xz yz +xlo_bound xhi_bound xy +ylo_bound yhi_bound xz +zlo_bound zhi_bound yz :pre + +This bounding box is convenient for many visualization programs and is +calculated from the 9 triclinic box parameters +(xlo,xhi,ylo,yhi,zlo,zhi,xy,xz,yz) as follows: + +xlo_bound = xlo + MIN(0.0,xy,xz,xy+xz) +xhi_bound = xhi + MAX(0.0,xy,xz,xy+xz) +ylo_bound = ylo + MIN(0.0,yz) +yhi_bound = yhi + MAX(0.0,yz) +zlo_bound = zlo +zhi_bound = zhi :pre + +These formulas can be inverted if you need to convert the bounding box +back into the triclinic box parameters, e.g. xlo = xlo_bound - +MIN(0.0,xy,xz,xy+xz). + +One use of triclinic simulation boxes is to model solid-state crystals +with triclinic symmetry. The "lattice"_lattice.html command can be +used with non-orthogonal basis vectors to define a lattice that will +tile a triclinic simulation box via the +"create_atoms"_create_atoms.html command. + +A second use is to run Parinello-Rahman dynamics via the "fix +npt"_fix_nh.html command, which will adjust the xy, xz, yz tilt +factors to compensate for off-diagonal components of the pressure +tensor. The analog for an "energy minimization"_minimize.html is +the "fix box/relax"_fix_box_relax.html command. + +A third use is to shear a bulk solid to study the response of the +material. The "fix deform"_fix_deform.html command can be used for +this purpose. It allows dynamic control of the xy, xz, yz tilt +factors as a simulation runs. This is discussed in the next section +on non-equilibrium MD (NEMD) simulations. diff --git a/doc/src/Howto_viscosity.txt b/doc/src/Howto_viscosity.txt new file mode 100644 index 0000000000..4760607fd5 --- /dev/null +++ b/doc/src/Howto_viscosity.txt @@ -0,0 +1,133 @@ +"Higher level section"_Howto.html - "LAMMPS WWW Site"_lws - "LAMMPS +Documentation"_ld - "LAMMPS Commands"_lc :c + +:link(lws,http://lammps.sandia.gov) +:link(ld,Manual.html) +:link(lc,Section_commands.html#comm) + +:line + +Calculate viscosity :h3 + +The shear viscosity eta of a fluid can be measured in at least 5 ways +using various options in LAMMPS. See the examples/VISCOSITY directory +for scripts that implement the 5 methods discussed here for a simple +Lennard-Jones fluid model. Also, see the "Howto +kappa"_Howto_kappa.html doc page for an analogous discussion for +thermal conductivity. + +Eta is a measure of the propensity of a fluid to transmit momentum in +a direction perpendicular to the direction of velocity or momentum +flow. Alternatively it is the resistance the fluid has to being +sheared. It is given by + +J = -eta grad(Vstream) + +where J is the momentum flux in units of momentum per area per time. +and grad(Vstream) is the spatial gradient of the velocity of the fluid +moving in another direction, normal to the area through which the +momentum flows. Viscosity thus has units of pressure-time. + +The first method is to perform a non-equilibrium MD (NEMD) simulation +by shearing the simulation box via the "fix deform"_fix_deform.html +command, and using the "fix nvt/sllod"_fix_nvt_sllod.html command to +thermostat the fluid via the SLLOD equations of motion. +Alternatively, as a second method, one or more moving walls can be +used to shear the fluid in between them, again with some kind of +thermostat that modifies only the thermal (non-shearing) components of +velocity to prevent the fluid from heating up. + +In both cases, the velocity profile setup in the fluid by this +procedure can be monitored by the "fix ave/chunk"_fix_ave_chunk.html +command, which determines grad(Vstream) in the equation above. +E.g. the derivative in the y-direction of the Vx component of fluid +motion or grad(Vstream) = dVx/dy. The Pxy off-diagonal component of +the pressure or stress tensor, as calculated by the "compute +pressure"_compute_pressure.html command, can also be monitored, which +is the J term in the equation above. See the "Howto +nemd"_Howto_nemd.html doc page for details on NEMD simulations. + +The third method is to perform a reverse non-equilibrium MD simulation +using the "fix viscosity"_fix_viscosity.html command which implements +the rNEMD algorithm of Muller-Plathe. Momentum in one dimension is +swapped between atoms in two different layers of the simulation box in +a different dimension. This induces a velocity gradient which can be +monitored with the "fix ave/chunk"_fix_ave_chunk.html command. +The fix tallies the cumulative momentum transfer that it performs. +See the "fix viscosity"_fix_viscosity.html command for details. + +The fourth method is based on the Green-Kubo (GK) formula which +relates the ensemble average of the auto-correlation of the +stress/pressure tensor to eta. This can be done in a fully +equilibrated simulation which is in contrast to the two preceding +non-equilibrium methods, where momentum flows continuously through the +simulation box. + +Here is an example input script that calculates the viscosity of +liquid Ar via the GK formalism: + +# Sample LAMMPS input script for viscosity of liquid Ar :pre + +units real +variable T equal 86.4956 +variable V equal vol +variable dt equal 4.0 +variable p equal 400 # correlation length +variable s equal 5 # sample interval +variable d equal $p*$s # dump interval :pre + +# convert from LAMMPS real units to SI :pre + +variable kB equal 1.3806504e-23 # \[J/K/] Boltzmann +variable atm2Pa equal 101325.0 +variable A2m equal 1.0e-10 +variable fs2s equal 1.0e-15 +variable convert equal $\{atm2Pa\}*$\{atm2Pa\}*$\{fs2s\}*$\{A2m\}*$\{A2m\}*$\{A2m\} :pre + +# setup problem :pre + +dimension 3 +boundary p p p +lattice fcc 5.376 orient x 1 0 0 orient y 0 1 0 orient z 0 0 1 +region box block 0 4 0 4 0 4 +create_box 1 box +create_atoms 1 box +mass 1 39.948 +pair_style lj/cut 13.0 +pair_coeff * * 0.2381 3.405 +timestep $\{dt\} +thermo $d :pre + +# equilibration and thermalization :pre + +velocity all create $T 102486 mom yes rot yes dist gaussian +fix NVT all nvt temp $T $T 10 drag 0.2 +run 8000 :pre + +# viscosity calculation, switch to NVE if desired :pre + +#unfix NVT +#fix NVE all nve :pre + +reset_timestep 0 +variable pxy equal pxy +variable pxz equal pxz +variable pyz equal pyz +fix SS all ave/correlate $s $p $d & + v_pxy v_pxz v_pyz type auto file S0St.dat ave running +variable scale equal $\{convert\}/($\{kB\}*$T)*$V*$s*$\{dt\} +variable v11 equal trap(f_SS\[3\])*$\{scale\} +variable v22 equal trap(f_SS\[4\])*$\{scale\} +variable v33 equal trap(f_SS\[5\])*$\{scale\} +thermo_style custom step temp press v_pxy v_pxz v_pyz v_v11 v_v22 v_v33 +run 100000 +variable v equal (v_v11+v_v22+v_v33)/3.0 +variable ndens equal count(all)/vol +print "average viscosity: $v \[Pa.s\] @ $T K, $\{ndens\} /A^3" :pre + +The fifth method is related to the above Green-Kubo method, +but uses the Einstein formulation, analogous to the Einstein +mean-square-displacement formulation for self-diffusivity. The +time-integrated momentum fluxes play the role of Cartesian +coordinates, whose mean-square displacement increases linearly +with time at sufficiently long times. diff --git a/doc/src/Howto_viz.txt b/doc/src/Howto_viz.txt new file mode 100644 index 0000000000..53635442c8 --- /dev/null +++ b/doc/src/Howto_viz.txt @@ -0,0 +1,40 @@ +"Higher level section"_Howto.html - "LAMMPS WWW Site"_lws - "LAMMPS +Documentation"_ld - "LAMMPS Commands"_lc :c + +:link(lws,http://lammps.sandia.gov) +:link(ld,Manual.html) +:link(lc,Section_commands.html#comm) + +:line + +Visualize LAMMPS snapshots :h3 + +LAMMPS itself does not do visualization, but snapshots from LAMMPS +simulations can be visualized (and analyzed) in a variety of ways. + +Mention dump image and dump movie. + +LAMMPS snapshots are created by the "dump"_dump.html command which can +create files in several formats. The native LAMMPS dump format is a +text file (see "dump atom" or "dump custom") which can be visualized +by several popular visualization tools. The "dump +image"_dump_image.html and "dump movie"_dump_image.html styles can +output internally rendered images and convert a sequence of them to a +movie during the MD run. Several programs included with LAMMPS as +auxiliary tools can convert between LAMMPS format files and other +formats. See the "Tools"_Tools.html doc page for details. + +A Python-based toolkit distributed by our group can read native LAMMPS +dump files, including custom dump files with additional columns of +user-specified atom information, and convert them to various formats +or pipe them into visualization software directly. See the "Pizza.py +WWW site"_pizza for details. Specifically, Pizza.py can convert +LAMMPS dump files into PDB, XYZ, "Ensight"_ensight, and VTK formats. +Pizza.py can pipe LAMMPS dump files directly into the Raster3d and +RasMol visualization programs. Pizza.py has tools that do interactive +3d OpenGL visualization and one that creates SVG images of dump file +snapshots. + +:link(pizza,http://www.sandia.gov/~sjplimp/pizza.html) +:link(ensight,http://www.ensight.com) +:link(atomeye,http://mt.seas.upenn.edu/Archive/Graphics/A) diff --git a/doc/src/Howto_walls.txt b/doc/src/Howto_walls.txt new file mode 100644 index 0000000000..7b0f8c0cfa --- /dev/null +++ b/doc/src/Howto_walls.txt @@ -0,0 +1,80 @@ +"Higher level section"_Howto.html - "LAMMPS WWW Site"_lws - "LAMMPS +Documentation"_ld - "LAMMPS Commands"_lc :c + +:link(lws,http://lammps.sandia.gov) +:link(ld,Manual.html) +:link(lc,Section_commands.html#comm) + +:line + +Walls :h3 + +Walls in an MD simulation are typically used to bound particle motion, +i.e. to serve as a boundary condition. + +Walls in LAMMPS can be of rough (made of particles) or idealized +surfaces. Ideal walls can be smooth, generating forces only in the +normal direction, or frictional, generating forces also in the +tangential direction. + +Rough walls, built of particles, can be created in various ways. The +particles themselves can be generated like any other particle, via the +"lattice"_lattice.html and "create_atoms"_create_atoms.html commands, +or read in via the "read_data"_read_data.html command. + +Their motion can be constrained by many different commands, so that +they do not move at all, move together as a group at constant velocity +or in response to a net force acting on them, move in a prescribed +fashion (e.g. rotate around a point), etc. Note that if a time +integration fix like "fix nve"_fix_nve.html or "fix nvt"_fix_nh.html +is not used with the group that contains wall particles, their +positions and velocities will not be updated. + +"fix aveforce"_fix_aveforce.html - set force on particles to average value, so they move together +"fix setforce"_fix_setforce.html - set force on particles to a value, e.g. 0.0 +"fix freeze"_fix_freeze.html - freeze particles for use as granular walls +"fix nve/noforce"_fix_nve_noforce.html - advect particles by their velocity, but without force +"fix move"_fix_move.html - prescribe motion of particles by a linear velocity, oscillation, rotation, variable :ul + +The "fix move"_fix_move.html command offers the most generality, since +the motion of individual particles can be specified with +"variable"_variable.html formula which depends on time and/or the +particle position. + +For rough walls, it may be useful to turn off pairwise interactions +between wall particles via the "neigh_modify +exclude"_neigh_modify.html command. + +Rough walls can also be created by specifying frozen particles that do +not move and do not interact with mobile particles, and then tethering +other particles to the fixed particles, via a "bond"_bond_style.html. +The bonded particles do interact with other mobile particles. + +Idealized walls can be specified via several fix commands. "Fix +wall/gran"_fix_wall_gran.html creates frictional walls for use with +granular particles; all the other commands create smooth walls. + +"fix wall/reflect"_fix_wall_reflect.html - reflective flat walls +"fix wall/lj93"_fix_wall.html - flat walls, with Lennard-Jones 9/3 potential +"fix wall/lj126"_fix_wall.html - flat walls, with Lennard-Jones 12/6 potential +"fix wall/colloid"_fix_wall.html - flat walls, with "pair_style colloid"_pair_colloid.html potential +"fix wall/harmonic"_fix_wall.html - flat walls, with repulsive harmonic spring potential +"fix wall/region"_fix_wall_region.html - use region surface as wall +"fix wall/gran"_fix_wall_gran.html - flat or curved walls with "pair_style granular"_pair_gran.html potential :ul + +The {lj93}, {lj126}, {colloid}, and {harmonic} styles all allow the +flat walls to move with a constant velocity, or oscillate in time. +The "fix wall/region"_fix_wall_region.html command offers the most +generality, since the region surface is treated as a wall, and the +geometry of the region can be a simple primitive volume (e.g. a +sphere, or cube, or plane), or a complex volume made from the union +and intersection of primitive volumes. "Regions"_region.html can also +specify a volume "interior" or "exterior" to the specified primitive +shape or {union} or {intersection}. "Regions"_region.html can also be +"dynamic" meaning they move with constant velocity, oscillate, or +rotate. + +The only frictional idealized walls currently in LAMMPS are flat or +curved surfaces specified by the "fix wall/gran"_fix_wall_gran.html +command. At some point we plan to allow regoin surfaces to be used as +frictional walls, as well as triangulated surfaces. diff --git a/doc/src/Intro.txt b/doc/src/Intro.txt new file mode 100644 index 0000000000..a634799721 --- /dev/null +++ b/doc/src/Intro.txt @@ -0,0 +1,43 @@ +"Previous Section"_Manual.html - "LAMMPS WWW Site"_lws - +"LAMMPS Documentation"_ld - "LAMMPS Commands"_lc - "Next +Section"_Section_start.html :c + +:link(lws,http://lammps.sandia.gov) +:link(ld,Manual.html) +:link(lc,Commands.html#comm) + +:line + +Introduction :h2 + +The "LAMMPS website"_lws is the best introduction to LAMMPS. + +Here is a list of webpages you can browse: + +"Brief intro and significant recent features"_lws +"List of features"_http://lammps.sandia.gov/features.html +"List of non-features"_http://lammps.sandia.gov/non_features.html +"Recent bug fixes and new features"_http://lammps.sandia.gov/bug.html :ul + +"Download info"_http://lammps.sandia.gov/download.html +"GitHub site"_https://github.com/lammps/lammps +"SourceForge site"_https://sourceforge.net/projects/lammps +"Open source and licensing info"_http://lammps.sandia.gov/open_source.html :ul + +"Glossary of MD terms relevant to LAMMPS"_http://lammps.sandia.gov/glossary.html +"LAMMPS highlights with images"_http://lammps.sandia.gov/pictures.html +"LAMMPS highlights with movies"_http://lammps.sandia.gov/movies.html +"Mail list"_http://lammps.sandia.gov/mail.html +"Workshops"_http://lammps.sandia.gov/workshops.html +"Tutorials"_http://lammps.sandia.gov/tutorials.html +"Developer guide"_http://lammps.sandia.gov/Developer.pdf :ul + +"Pre- and post-processing tools for LAMMPS"_http://lammps.sandia.gov/prepost.html +"Other software usable with LAMMPS"_http://lammps.sandia.gov/offsite.html +"Viz tools usable with LAMMPS"_http://lammps.sandia.gov/viz.html :ul + +"Benchmark performance"_http://lammps.sandia.gov/bench.html +"Publications that have cited LAMMPS"_http://lammps.sandia.gov/papers.html +"Authors of the LAMMPS code"_http://lammps.sandia.gov/authors.html +"History of LAMMPS development"_http://lammps.sandia.gov/history.html +"Funding for LAMMPS"_http://lammps.sandia.gov/funding.html :ul diff --git a/doc/src/Manual.txt b/doc/src/Manual.txt index 31b8a6a1d4..3fe5a25fbb 100644 --- a/doc/src/Manual.txt +++ b/doc/src/Manual.txt @@ -1,5 +1,5 @@ -< + LAMMPS Users Manual @@ -18,87 +18,47 @@ :line +

+ LAMMPS Documentation :c,h1 -16 Jul 2018 version :c,h2 +16 Mar 2018 version :c,h2 -Version info: :h3 - -The LAMMPS "version" is the date when it was released, such as 1 May -2010. LAMMPS is updated continuously. Whenever we fix a bug or add a -feature, we release it immediately, and post a notice on "this page of -the WWW site"_bug. Every 2-4 months one of the incremental releases -is subjected to more thorough testing and labeled as a {stable} version. - -Each dated copy of LAMMPS contains all the -features and bug-fixes up to and including that version date. The -version date is printed to the screen and logfile every time you run -LAMMPS. It is also in the file src/version.h and in the LAMMPS -directory name created when you unpack a tarball, and at the top of -the first page of the manual (this page). - -If you browse the HTML doc pages on the LAMMPS WWW site, they always -describe the most current [development] version of LAMMPS. :ulb,l - -If you browse the HTML doc pages included in your tarball, they -describe the version you have. :l - -The "PDF file"_Manual.pdf on the WWW site or in the tarball is updated -about once per month. This is because it is large, and we don't want -it to be part of every patch. :l - -There is also a "Developer.pdf"_Developer.pdf file in the doc -directory, which describes the internal structure and algorithms of -LAMMPS. :l -:ule +"What is a LAMMPS version?"_Manual_version.html LAMMPS stands for Large-scale Atomic/Molecular Massively Parallel Simulator. LAMMPS is a classical molecular dynamics simulation code designed to -run efficiently on parallel computers. It was developed at Sandia -National Laboratories, a US Department of Energy facility, with +run efficiently on parallel computers. It was developed originally at +Sandia National Laboratories, a US Department of Energy facility, with funding from the DOE. It is an open-source code, distributed freely under the terms of the GNU Public License (GPL). -The current core group of LAMMPS developers is at Sandia National -Labs and Temple University: - -"Steve Plimpton"_sjp, sjplimp at sandia.gov :ulb,l -Aidan Thompson, athomps at sandia.gov :l -Stan Moore, stamoor at sandia.gov :l -"Axel Kohlmeyer"_ako, akohlmey at gmail.com :l -:ule - -Past core developers include Paul Crozier, Ray Shan and Mark Stevens, -all at Sandia. The [LAMMPS home page] at -"http://lammps.sandia.gov"_http://lammps.sandia.gov has more information -about the code and its uses. Interaction with external LAMMPS developers, -bug reports and feature requests are mainly coordinated through the -"LAMMPS project on GitHub."_https://github.com/lammps/lammps -The lammps.org domain, currently hosting "public continuous integration -testing"_https://ci.lammps.org/job/lammps/ and "precompiled Linux -RPM and Windows installer packages"_http://packages.lammps.org is located -at Temple University and managed by Richard Berger, -richard.berger at temple.edu. - -:link(bug,http://lammps.sandia.gov/bug.html) -:link(sjp,http://www.sandia.gov/~sjplimp) -:link(ako,http://goo.gl/1wk0) +The "LAMMPS website"_lws has information about the code authors, a +"mail list"_http://lammps.sandia.gov where users can post questions, +and a "GitHub site"https://github.com/lammps/lammps where all LAMMPS +development is coordinated. :line -The LAMMPS documentation is organized into the following sections. If -you find errors or omissions in this manual or have suggestions for -useful information to add, please send an email to the developers so -we can improve the LAMMPS documentation. - -Once you are familiar with LAMMPS, you may want to bookmark "this -page"_Section_commands.html#comm at Section_commands.html#comm since -it gives quick access to documentation for all LAMMPS commands. - "PDF file"_Manual.pdf of the entire manual, generated by "htmldoc"_http://freecode.com/projects/htmldoc +The content for this manual is part of the LAMMPS distribution. +You can build a local copy of the Manual as HTML pages or a PDF file, +by following the steps on the "this page"_Build_manual.html. + +There is also a "Developer.pdf"_Developer.pdf document which gives +a brief description of the basic code structure of LAMMPS. + +:line + +This manual is organized into the following sections. + +Once you are familiar with LAMMPS, you may want to bookmark "this +page"_Commands.html since it gives quick access to a doc page for +every LAMMPS command. + -"Introduction"_Section_intro.html :olb,l - 1.1 "What is LAMMPS"_intro_1 :ulb,b - 1.2 "LAMMPS features"_intro_2 :b - 1.3 "LAMMPS non-features"_intro_3 :b - 1.4 "Open source distribution"_intro_4 :b - 1.5 "Acknowledgments and citations"_intro_5 :ule,b +"Introduction"_Intro.html :olb,l "Getting started"_Section_start.html :l 2.1 "What's in the LAMMPS distribution"_start_1 :ulb,b 2.2 "Making LAMMPS"_start_2 :b @@ -168,50 +121,14 @@ END_RST --> 3.5 "Commands listed alphabetically"_cmd_5 :ule,b "Optional packages"_Packages.html :l "Accelerate performance"_Speed.html :l -"How-to discussions"_Section_howto.html :l - 6.1 "Restarting a simulation"_howto_1 :ulb,b - 6.2 "2d simulations"_howto_2 :b - 6.3 "CHARMM and AMBER force fields"_howto_3 :b - 6.4 "Running multiple simulations from one input script"_howto_4 :b - 6.5 "Multi-replica simulations"_howto_5 :b - 6.6 "Granular models"_howto_6 :b - 6.7 "TIP3P water model"_howto_7 :b - 6.8 "TIP4P water model"_howto_8 :b - 6.9 "SPC water model"_howto_9 :b - 6.10 "Coupling LAMMPS to other codes"_howto_10 :b - 6.11 "Visualizing LAMMPS snapshots"_howto_11 :b - 6.12 "Triclinic (non-orthogonal) simulation boxes"_howto_12 :b - 6.13 "NEMD simulations"_howto_13 :b - 6.14 "Finite-size spherical and aspherical particles"_howto_14 :b - 6.15 "Output from LAMMPS (thermo, dumps, computes, fixes, variables)"_howto_15 :b - 6.16 "Thermostatting, barostatting, and compute temperature"_howto_16 :b - 6.17 "Walls"_howto_17 :b - 6.18 "Elastic constants"_howto_18 :b - 6.19 "Library interface to LAMMPS"_howto_19 :b - 6.20 "Calculating thermal conductivity"_howto_20 :b - 6.21 "Calculating viscosity"_howto_21 :b - 6.22 "Calculating a diffusion coefficient"_howto_22 :b - 6.23 "Using chunks to calculate system properties"_howto_23 :b - 6.24 "Setting parameters for pppm/disp"_howto_24 :b - 6.25 "Polarizable models"_howto_25 :b - 6.26 "Adiabatic core/shell model"_howto_26 :b - 6.27 "Drude induced dipoles"_howto_27 :ule,b +"How-to discussions"_Howto.html :l "Example scripts"_Examples.html :l "Auxiliary tools"_Tools.html :l "Modify & extend LAMMPS"_Modify.html :l "Use Python with LAMMPS"_Python.html :l "Errors"_Errors.html :l -"Future and history"_Section_history.html :l - 13.1 "Coming attractions"_hist_1 :ulb,b - 13.2 "Past versions"_hist_2 :ule,b :ole -:link(intro_1,Section_intro.html#intro_1) -:link(intro_2,Section_intro.html#intro_2) -:link(intro_3,Section_intro.html#intro_3) -:link(intro_4,Section_intro.html#intro_4) -:link(intro_5,Section_intro.html#intro_5) - :link(start_1,Section_start.html#start_1) :link(start_2,Section_start.html#start_2) :link(start_3,Section_start.html#start_3) @@ -227,36 +144,6 @@ END_RST --> :link(cmd_4,Section_commands.html#cmd_4) :link(cmd_5,Section_commands.html#cmd_5) -:link(howto_1,Section_howto.html#howto_1) -:link(howto_2,Section_howto.html#howto_2) -:link(howto_3,Section_howto.html#howto_3) -:link(howto_4,Section_howto.html#howto_4) -:link(howto_5,Section_howto.html#howto_5) -:link(howto_6,Section_howto.html#howto_6) -:link(howto_7,Section_howto.html#howto_7) -:link(howto_8,Section_howto.html#howto_8) -:link(howto_9,Section_howto.html#howto_9) -:link(howto_10,Section_howto.html#howto_10) -:link(howto_11,Section_howto.html#howto_11) -:link(howto_12,Section_howto.html#howto_12) -:link(howto_13,Section_howto.html#howto_13) -:link(howto_14,Section_howto.html#howto_14) -:link(howto_15,Section_howto.html#howto_15) -:link(howto_16,Section_howto.html#howto_16) -:link(howto_17,Section_howto.html#howto_17) -:link(howto_18,Section_howto.html#howto_18) -:link(howto_19,Section_howto.html#howto_19) -:link(howto_20,Section_howto.html#howto_20) -:link(howto_21,Section_howto.html#howto_21) -:link(howto_22,Section_howto.html#howto_22) -:link(howto_23,Section_howto.html#howto_23) -:link(howto_24,Section_howto.html#howto_24) -:link(howto_25,Section_howto.html#howto_25) -:link(howto_26,Section_howto.html#howto_26) -:link(howto_27,Section_howto.html#howto_27) - -:link(hist_1,Section_history.html#hist_1) -:link(hist_2,Section_history.html#hist_2) diff --git a/doc/src/Manual_version.txt b/doc/src/Manual_version.txt new file mode 100644 index 0000000000..db4301b6ea --- /dev/null +++ b/doc/src/Manual_version.txt @@ -0,0 +1,33 @@ +"Higher level section"_Manual.html - "LAMMPS WWW Site"_lws - "LAMMPS +Documentation"_ld - "LAMMPS Commands"_lc :c + +:link(lws,http://lammps.sandia.gov) +:link(ld,Manual.html) +:link(lc,Section_commands.html#comm) + +:line + +What does a LAMMPS version mean: :h3 + +The LAMMPS "version" is the date when it was released, such as 1 May +2014. LAMMPS is updated continuously. Whenever we fix a bug or add a +feature, we release it in the next {patch} release, which are +typically made every couple of weeks. Info on patch releases are on +"this website page"_http://lammps.sandia.gov/bug.html. Every few +months, the latest patch release is subjected to more thorough testing +and labeled as a {stable} version. + +Each version of LAMMPS contains all the features and bug-fixes up to +and including its version date. + +The version date is printed to the screen and logfile every time you +run LAMMPS. It is also in the file src/version.h and in the LAMMPS +directory name created when you unpack a tarball. And it is on the +first page of the "manual"_Manual.html. + +If you browse the HTML doc pages on the LAMMPS WWW site, they always +describe the most current patch release of LAMMPS. :ulb,l + +If you browse the HTML doc pages included in your tarball, they +describe the version you have, which may be older. :l,ule + diff --git a/doc/src/Modify_body.txt b/doc/src/Modify_body.txt index b1dc8130cd..a0627ebdda 100644 --- a/doc/src/Modify_body.txt +++ b/doc/src/Modify_body.txt @@ -14,10 +14,9 @@ Body particles can represent complex entities, such as surface meshes of discrete points, collections of sub-particles, deformable objects, etc. -See "Section 6.14"_Section_howto.html#howto_14 of the manual for -an overview of using body particles and the "body"_body.html doc page -for details on the various body styles LAMMPS supports. New styles -can be created to add new kinds of body particles to LAMMPS. +See the "Howto body"_Howto_body.html doc page for an overview of using +body particles and the various body styles LAMMPS supports. New +styles can be created to add new kinds of body particles to LAMMPS. Body_nparticle.cpp is an example of a body particle that is treated as a rigid body containing N sub-particles. diff --git a/doc/src/Modify_contribute.txt b/doc/src/Modify_contribute.txt index 80795b5e20..9d47b08251 100644 --- a/doc/src/Modify_contribute.txt +++ b/doc/src/Modify_contribute.txt @@ -32,14 +32,14 @@ How quickly your contribution will be integrated depends largely on how much effort it will cause to integrate and test it, how much it requires changes to the core codebase, and of how much interest it is to the larger LAMMPS community. Please see below for a checklist of -typical requirements. Once you have prepared everything, see "this -tutorial"_tutorial_github.html for instructions on how to submit your -changes or new files through a GitHub pull request. If you prefer to -submit patches or full files, you should first make certain, that your -code works correctly with the latest patch-level version of LAMMPS and -contains all bugfixes from it. Then create a gzipped tar file of all -changed or added files or a corresponding patch file using 'diff -u' -or 'diff -c' and compress it with gzip. Please only use gzip +typical requirements. Once you have prepared everything, see the +"Howto github"_Howto_github.html doc page for instructions on how to +submit your changes or new files through a GitHub pull request. If you +prefer to submit patches or full files, you should first make certain, +that your code works correctly with the latest patch-level version of +LAMMPS and contains all bugfixes from it. Then create a gzipped tar +file of all changed or added files or a corresponding patch file using +'diff -u' or 'diff -c' and compress it with gzip. Please only use gzip compression, as this works well on all platforms. If the new features/files are broadly useful we may add them as core @@ -54,8 +54,9 @@ packages by typing "make package" in the LAMMPS src directory. Note that by providing us files to release, you are agreeing to make them open-source, i.e. we can release them under the terms of the GPL, -used as a license for the rest of LAMMPS. See "Section -1.4"_Section_intro.html#intro_4 for details. +used as a license for the rest of LAMMPS. See the "Open +source"_http://lammps.sandia.gov/open_source.html page on the LAMMPS +website for details. With user packages and files, all we are really providing (aside from the fame and fortune that accompanies having your name in the source diff --git a/doc/src/Packages_details.txt b/doc/src/Packages_details.txt index af18d097d9..543578054c 100644 --- a/doc/src/Packages_details.txt +++ b/doc/src/Packages_details.txt @@ -112,7 +112,7 @@ make machine :pre [Supporting info:] src/ASPHERE: filenames -> commands -"Section 6.14"_Section_howto.html#howto_14 +"Howto spherical"_Howto_spherical.html "pair_style gayberne"_pair_gayberne.html "pair_style resquared"_pair_resquared.html "doc/PDF/pair_gayberne_extra.pdf"_PDF/pair_gayberne_extra.pdf @@ -130,7 +130,8 @@ BODY package :link(BODY),h4 Body-style particles with internal structure. Computes, time-integration fixes, pair styles, as well as the body styles -themselves. See the "body"_body.html doc page for an overview. +themselves. See the "Howto body"_Howto_body.html doc page for an +overview. [Install or un-install:] @@ -143,7 +144,7 @@ make machine :pre [Supporting info:] src/BODY filenames -> commands -"body"_body.html +"Howto_body"_Howto_body.html "atom_style body"_atom_style.html "fix nve/body"_fix_nve_body.html "pair_style body"_pair_body.html @@ -258,9 +259,9 @@ Compute and pair styles that implement the adiabatic core/shell model for polarizability. The pair styles augment Born, Buckingham, and Lennard-Jones styles with core/shell capabilities. The "compute temp/cs"_compute_temp_cs.html command calculates the temperature of a -system with core/shell particles. See "Section -6.26"_Section_howto.html#howto_26 for an overview of how to use this -package. +system with core/shell particles. See the "Howto +coreshell"_Howto_coreshell.html doc page for an overview of how to use +this package. [Author:] Hendrik Heenen (Technical U of Munich). @@ -275,8 +276,8 @@ make machine :pre [Supporting info:] src/CORESHELL: filenames -> commands -"Section 6.26"_Section_howto.html#howto_26 -"Section 6.25"_Section_howto.html#howto_25 +"Howto coreshell"_Howto_coreshell.html +"Howto polarizable"_Howto_polarizable.html "compute temp/cs"_compute_temp_cs.html "pair_style born/coul/long/cs"_pair_cs.html "pair_style buck/coul/long/cs"_pair_cs.html @@ -418,7 +419,7 @@ make machine :pre [Supporting info:] src/GRANULAR: filenames -> commands -"Section 6.6"_Section_howto.html#howto_6, +"Howto granular"_Howto_granular.html "fix pour"_fix_pour.html "fix wall/gran"_fix_wall_gran.html "pair_style gran/hooke"_pair_gran.html @@ -625,9 +626,9 @@ make machine :pre src/KSPACE: filenames -> commands "kspace_style"_kspace_style.html "doc/PDF/kspace.pdf"_PDF/kspace.pdf -"Section 6.7"_Section_howto.html#howto_7 -"Section 6.8"_Section_howto.html#howto_8 -"Section 6.9"_Section_howto.html#howto_9 +"Howto tip3p"_Howto_tip3p.html +"Howto tip4p"_Howto_tip4p.html +"Howto spc"_Howto_spc.html "pair_style coul"_pair_coul.html Pair Styles section of "Section 3.5"_Section_commands.html#cmd_5 with "long" or "msm" in pair style name examples/peptide @@ -876,7 +877,7 @@ src/MOLECULE: filenames -> commands "improper_style"_improper_style.html "pair_style hbond/dreiding/lj"_pair_hbond_dreiding.html "pair_style lj/charmm/coul/charmm"_pair_charmm.html -"Section 6.3"_Section_howto.html#howto_3 +"Howto bioFF"_Howto_bioFF.html examples/cmap examples/dreiding examples/micelle, @@ -1114,10 +1115,10 @@ PYTHON package :link(PYTHON),h4 A "python"_python.html command which allow you to execute Python code from a LAMMPS input script. The code can be in a separate file or -embedded in the input script itself. See "Section -11.2"_Section_python.html#py_2 for an overview of using Python from -LAMMPS in this manner and the entire section for other ways to use -LAMMPS and Python together. +embedded in the input script itself. See the "Python +call"_Python_call.html doc page for an overview of using Python from +LAMMPS in this manner and all the "Python"_Python.html doc pages for +other ways to use LAMMPS and Python together. [Install or un-install:] @@ -1138,7 +1139,7 @@ to Makefile.lammps) if the LAMMPS build fails. [Supporting info:] src/PYTHON: filenames -> commands -"Section 11"_Section_python.html +"Python call"_Python.html lib/python/README examples/python :ul @@ -1228,8 +1229,8 @@ REPLICA package :link(REPLICA),h4 [Contents:] A collection of multi-replica methods which can be used when running -multiple LAMMPS simulations (replicas). See "Section -6.5"_Section_howto.html#howto_5 for an overview of how to run +multiple LAMMPS simulations (replicas). See the "Howto +replica"_Howto_replica.html doc page for an overview of how to run multi-replica simulations in LAMMPS. Methods in the package include nudged elastic band (NEB), parallel replica dynamics (PRD), temperature accelerated dynamics (TAD), parallel tempering, and a @@ -1248,7 +1249,7 @@ make machine :pre [Supporting info:] src/REPLICA: filenames -> commands -"Section 6.5"_Section_howto.html#howto_5 +"Howto replica"_Howto_replica.html "neb"_neb.html "prd"_prd.html "tad"_tad.html @@ -1798,10 +1799,10 @@ USER-DRUDE package :link(USER-DRUDE),h4 [Contents:] Fixes, pair styles, and a compute to simulate thermalized Drude -oscillators as a model of polarization. See "Section -6.27"_Section_howto.html#howto_27 for an overview of how to use the -package. There are auxiliary tools for using this package in -tools/drude. +oscillators as a model of polarization. See the "Howto +drude"_Howto_drude.html and "Howto drude2"_Howto_drude2.html doc pages +for an overview of how to use the package. There are auxiliary tools +for using this package in tools/drude. [Authors:] Alain Dequidt (U Blaise Pascal Clermont-Ferrand), Julien Devemy (CNRS), and Agilio Padua (U Blaise Pascal). @@ -1817,8 +1818,9 @@ make machine :pre [Supporting info:] src/USER-DRUDE: filenames -> commands -"Section 6.27"_Section_howto.html#howto_27 -"Section 6.25"_Section_howto.html#howto_25 +"Howto drude"_Howto_drude.html +"Howto drude2"_Howto_drude2.html +"Howto polarizable"_Howto_polarizable.html src/USER-DRUDE/README "fix drude"_fix_drude.html "fix drude/transform/*"_fix_drude_transform.html @@ -2158,7 +2160,7 @@ make machine :pre src/USER-MANIFOLD: filenames -> commands src/USER-MANIFOLD/README -"doc/manifolds"_manifolds.html +"Howto manifold"_Howto_manifold.html "fix manifoldforce"_fix_manifoldforce.html "fix nve/manifold/rattle"_fix_nve_manifold_rattle.html "fix nvt/manifold/rattle"_fix_nvt_manifold_rattle.html diff --git a/doc/src/Packages_standard.txt b/doc/src/Packages_standard.txt index 095bf699a6..b2c06eebfd 100644 --- a/doc/src/Packages_standard.txt +++ b/doc/src/Packages_standard.txt @@ -31,15 +31,15 @@ int = internal library: provided with LAMMPS, but you may need to build it ext = external library: you will need to download and install it on your machine :ul Package, Description, Doc page, Example, Library -"ASPHERE"_Packages_details.html#ASPHERE, aspherical particle models, "Section 6.6.14"_Section_howto.html#howto_14, ellipse, - -"BODY"_Packages_details.html#BODY, body-style particles, "body"_body.html, body, - +"ASPHERE"_Packages_details.html#ASPHERE, aspherical particle models, "Howto spherical"_Howto_spherical.html, ellipse, - +"BODY"_Packages_details.html#BODY, body-style particles, "Howto body"_Howto_body.html, body, - "CLASS2"_Packages_details.html#CLASS2, class 2 force fields, "pair_style lj/class2"_pair_class2.html, -, - "COLLOID"_Packages_details.html#COLLOID, colloidal particles, "atom_style colloid"_atom_style.html, colloid, - "COMPRESS"_Packages_details.html#COMPRESS, I/O compression, "dump */gz"_dump.html, -, sys -"CORESHELL"_Packages_details.html#CORESHELL, adiabatic core/shell model, "Section 6.6.25"_Section_howto.html#howto_25, coreshell, - +"CORESHELL"_Packages_details.html#CORESHELL, adiabatic core/shell model, "Howto coreshell"_Howto_coreshell.html, coreshell, - "DIPOLE"_Packages_details.html#DIPOLE, point dipole particles, "pair_style dipole/cut"_pair_dipole.html, dipole, - "GPU"_Packages_details.html#GPU, GPU-enabled styles, "Section gpu"_Speed_gpu.html, "Benchmarks"_http://lammps.sandia.gov/bench.html, int -"GRANULAR"_Packages_details.html#GRANULAR, granular systems, "Section 6.6.6"_Section_howto.html#howto_6, pour, - +"GRANULAR"_Packages_details.html#GRANULAR, granular systems, "Howto granular"_Howto_granular.html, pour, - "KIM"_Packages_details.html#KIM, OpenKIM wrapper, "pair_style kim"_pair_kim.html, kim, ext "KOKKOS"_Packages_details.html#KOKKOS, Kokkos-enabled styles, "Speed kokkos"_Speed_kokkos.html, "Benchmarks"_http://lammps.sandia.gov/bench.html, - "KSPACE"_Packages_details.html#KSPACE, long-range Coulombic solvers, "kspace_style"_kspace_style.html, peptide, - @@ -48,7 +48,7 @@ Package, Description, Doc page, Example, Library "MC"_Packages_details.html#MC, Monte Carlo options, "fix gcmc"_fix_gcmc.html, -, - "MEAM"_Packages_details.html#MEAM, modified EAM potential, "pair_style meam"_pair_meam.html, meam, int "MISC"_Packages_details.html#MISC, miscellanous single-file commands, -, -, - -"MOLECULE"_Packages_details.html#MOLECULE, molecular system force fields, "Section 6.6.3"_Section_howto.html#howto_3, peptide, - +"MOLECULE"_Packages_details.html#MOLECULE, molecular system force fields, "Howto bioFF"_Howto_bioFF.html, peptide, - "MPIIO"_Packages_details.html#MPIIO, MPI parallel I/O dump and restart, "dump"_dump.html, -, - "MSCG"_Packages_details.html#MSCG, multi-scale coarse-graining wrapper, "fix mscg"_fix_mscg.html, mscg, ext "OPT"_Packages_details.html#OPT, optimized pair styles, "Speed opt"_Speed_opt.html, "Benchmarks"_http://lammps.sandia.gov/bench.html, - @@ -57,7 +57,7 @@ Package, Description, Doc page, Example, Library "PYTHON"_Packages_details.html#PYTHON, embed Python code in an input script, "python"_python.html, python, sys "QEQ"_Packages_details.html#QEQ, QEq charge equilibration, "fix qeq"_fix_qeq.html, qeq, - "REAX"_Packages_details.html#REAX, ReaxFF potential (Fortran), "pair_style reax"_pair_reax.html, reax, int -"REPLICA"_Packages_details.html#REPLICA, multi-replica methods, "Section 6.6.5"_Section_howto.html#howto_5, tad, - +"REPLICA"_Packages_details.html#REPLICA, multi-replica methods, "Howto replica"_Howto_replica.html, tad, - "RIGID"_Packages_details.html#RIGID, rigid bodies and constraints, "fix rigid"_fix_rigid.html, rigid, - "SHOCK"_Packages_details.html#SHOCK, shock loading methods, "fix msst"_fix_msst.html, -, - "SNAP"_Packages_details.html#SNAP, quantum-fitted potential, "pair_style snap"_pair_snap.html, snap, - diff --git a/doc/src/Packages_user.txt b/doc/src/Packages_user.txt index 73c7fdb65d..0465296980 100644 --- a/doc/src/Packages_user.txt +++ b/doc/src/Packages_user.txt @@ -46,7 +46,7 @@ Package, Description, Doc page, Example, Library "USER-COLVARS"_Packages_details.html#USER-COLVARS, collective variables library, "fix colvars"_fix_colvars.html, USER/colvars, int "USER-DIFFRACTION"_Packages_details.html#USER-DIFFRACTION, virtual x-ray and electron diffraction,"compute xrd"_compute_xrd.html, USER/diffraction, - "USER-DPD"_Packages_details.html#USER-DPD, reactive dissipative particle dynamics, src/USER-DPD/README, USER/dpd, - -"USER-DRUDE"_Packages_details.html#USER-DRUDE, Drude oscillators, "tutorial"_tutorial_drude.html, USER/drude, - +"USER-DRUDE"_Packages_details.html#USER-DRUDE, Drude oscillators, "Howto drude"_Howto_drude.html, USER/drude, - "USER-EFF"_Packages_details.html#USER-EFF, electron force field,"pair_style eff/cut"_pair_eff.html, USER/eff, - "USER-FEP"_Packages_details.html#USER-FEP, free energy perturbation,"compute fep"_compute_fep.html, USER/fep, - "USER-H5MD"_Packages_details.html#USER-H5MD, dump output via HDF5,"dump h5md"_dump_h5md.html, -, ext diff --git a/doc/src/Python_library.txt b/doc/src/Python_library.txt index 4babbb746c..db16c39a47 100644 --- a/doc/src/Python_library.txt +++ b/doc/src/Python_library.txt @@ -21,8 +21,8 @@ from lammps import lammps :pre These are the methods defined by the lammps module. If you look at the files src/library.cpp and src/library.h you will see they correspond one-to-one with calls you can make to the LAMMPS library -from a C++ or C or Fortran program, and which are described in -"Section 6.19"_Section_howto.html#howto_19 of the manual. +from a C++ or C or Fortran program, and which are described on the +"Howto library"_Howto_library.html doc page. The python/examples directory has Python scripts which show how Python can run LAMMPS, grab data, change it, and put it back into LAMMPS. @@ -165,11 +165,11 @@ subscripting. The one exception is that for a fix that calculates a global vector or array, a single double value from the vector or array is returned, indexed by I (vector) or I and J (array). I,J are zero-based indices. The I,J arguments can be left out if not needed. -See "Section 6.15"_Section_howto.html#howto_15 of the manual for a -discussion of global, per-atom, and local data, and of scalar, vector, -and array data types. See the doc pages for individual -"computes"_compute.html and "fixes"_fix.html for a description of what -they calculate and store. +See the "Howto output"_Howto_output.html doc page for a discussion of +global, per-atom, and local data, and of scalar, vector, and array +data types. See the doc pages for individual "computes"_compute.html +and "fixes"_fix.html for a description of what they calculate and +store. For extract_variable(), an "equal-style or atom-style variable"_variable.html is evaluated and its result returned. diff --git a/doc/src/Python_pylammps.txt b/doc/src/Python_pylammps.txt index ad5ed192ee..cdc8e2c086 100644 --- a/doc/src/Python_pylammps.txt +++ b/doc/src/Python_pylammps.txt @@ -10,5 +10,5 @@ Documentation"_ld - "LAMMPS Commands"_lc :c PyLammps interface :h3 PyLammps is a Python wrapper class which can be created on its own or -use an existing lammps Python object. It has its own "PyLammps -Tutorial"_tutorial_pylammps.html doc page. +use an existing lammps Python object. It has its own "Howto +pylammps"_Howto_pylammps.html doc page. diff --git a/doc/src/Section_history.txt b/doc/src/Section_history.txt deleted file mode 100644 index 6bbd1e4d99..0000000000 --- a/doc/src/Section_history.txt +++ /dev/null @@ -1,135 +0,0 @@ -"Previous Section"_Errors.html - "LAMMPS WWW Site"_lws - -"LAMMPS Documentation"_ld - "LAMMPS Commands"_lc - "Next -Section"_Manual.html :c - -:link(lws,http://lammps.sandia.gov) -:link(ld,Manual.html) -:link(lc,Section_commands.html#comm) - -:line - -13. Future and history :h2 - -This section lists features we plan to add to LAMMPS, features of -previous versions of LAMMPS, and features of other parallel molecular -dynamics codes our group has distributed. - -13.1 "Coming attractions"_#hist_1 -13.2 "Past versions"_#hist_2 :all(b) - -:line -:line - -13.1 Coming attractions :h3,link(hist_1) - -As of summer 2016 we are using the "LAMMPS project issue tracker -on GitHub"_https://github.com/lammps/lammps/issues for keeping -track of suggested, planned or pending new features. This includes -discussions of how to best implement them, or why they would be -useful. Especially if a planned or proposed feature is non-trivial -to add, e.g. because it requires changes to some of the core -classes of LAMMPS, people planning to contribute a new feature to -LAMMS are encouraged to submit an issue about their planned -implementation this way in order to receive feedback from the -LAMMPS core developers. They will provide suggestions about -the validity of the proposed approach and possible improvements, -pitfalls or alternatives. - -Please see some of the closed issues for examples of how to -suggest code enhancements, submit proposed changes, or report -possible bugs and how they are resolved. - -As an alternative to using GitHub, you may e-mail the -"core developers"_http://lammps.sandia.gov/authors.html or send -an e-mail to the "LAMMPS Mail list"_http://lammps.sandia.gov/mail.html -if you want to have your suggestion added to the list. - -:line - -13.2 Past versions :h3,link(hist_2) - -LAMMPS development began in the mid 1990s under a cooperative research -& development agreement (CRADA) between two DOE labs (Sandia and LLNL) -and 3 companies (Cray, Bristol Myers Squibb, and Dupont). The goal was -to develop a large-scale parallel classical MD code; the coding effort -was led by Steve Plimpton at Sandia. - -After the CRADA ended, a final F77 version, LAMMPS 99, was -released. As development of LAMMPS continued at Sandia, its memory -management was converted to F90; a final F90 version was released as -LAMMPS 2001. - -The current LAMMPS is a rewrite in C++ and was first publicly released -as an open source code in 2004. It includes many new features beyond -those in LAMMPS 99 or 2001. It also includes features from older -parallel MD codes written at Sandia, namely ParaDyn, Warp, and -GranFlow (see below). - -In late 2006 we began merging new capabilities into LAMMPS that were -developed by Aidan Thompson at Sandia for his MD code GRASP, which has -a parallel framework similar to LAMMPS. Most notably, these have -included many-body potentials - Stillinger-Weber, Tersoff, ReaxFF - -and the associated charge-equilibration routines needed for ReaxFF. - -The "History link"_http://lammps.sandia.gov/history.html on the -LAMMPS WWW page gives a timeline of features added to the -C++ open-source version of LAMMPS over the last several years. - -These older codes are available for download from the "LAMMPS WWW -site"_lws, except for Warp & GranFlow which were primarily used -internally. A brief listing of their features is given here. - -LAMMPS 2001 - - F90 + MPI - dynamic memory - spatial-decomposition parallelism - NVE, NVT, NPT, NPH, rRESPA integrators - LJ and Coulombic pairwise force fields - all-atom, united-atom, bead-spring polymer force fields - CHARMM-compatible force fields - class 2 force fields - 3d/2d Ewald & PPPM - various force and temperature constraints - SHAKE - Hessian-free truncated-Newton minimizer - user-defined diagnostics :ul - -LAMMPS 99 - - F77 + MPI - static memory allocation - spatial-decomposition parallelism - most of the LAMMPS 2001 features with a few exceptions - no 2d Ewald & PPPM - molecular force fields are missing a few CHARMM terms - no SHAKE :ul - -Warp - - F90 + MPI - spatial-decomposition parallelism - embedded atom method (EAM) metal potentials + LJ - lattice and grain-boundary atom creation - NVE, NVT integrators - boundary conditions for applying shear stresses - temperature controls for actively sheared systems - per-atom energy and centro-symmetry computation and output :ul - -ParaDyn - - F77 + MPI - atom- and force-decomposition parallelism - embedded atom method (EAM) metal potentials - lattice atom creation - NVE, NVT, NPT integrators - all serial DYNAMO features for controls and constraints :ul - -GranFlow - - F90 + MPI - spatial-decomposition parallelism - frictional granular potentials - NVE integrator - boundary conditions for granular flow and packing and walls - particle insertion :ul diff --git a/doc/src/Section_howto.txt b/doc/src/Section_howto.txt deleted file mode 100644 index f929d3bdab..0000000000 --- a/doc/src/Section_howto.txt +++ /dev/null @@ -1,3011 +0,0 @@ -"Previous Section"_Speed.html - "LAMMPS WWW Site"_lws - "LAMMPS Documentation"_ld - "LAMMPS Commands"_lc - "Next Section"_Examples.html :c - -:link(lws,http://lammps.sandia.gov) -:link(ld,Manual.html) -:link(lc,Section_commands.html#comm) - -:line - -6. How-to discussions :h2 - -This section describes how to perform common tasks using LAMMPS. - -6.1 "Restarting a simulation"_#howto_1 -6.2 "2d simulations"_#howto_2 -6.3 "CHARMM, AMBER, and DREIDING force fields"_#howto_3 -6.4 "Running multiple simulations from one input script"_#howto_4 -6.5 "Multi-replica simulations"_#howto_5 -6.6 "Granular models"_#howto_6 -6.7 "TIP3P water model"_#howto_7 -6.8 "TIP4P water model"_#howto_8 -6.9 "SPC water model"_#howto_9 -6.10 "Coupling LAMMPS to other codes"_#howto_10 -6.11 "Visualizing LAMMPS snapshots"_#howto_11 -6.12 "Triclinic (non-orthogonal) simulation boxes"_#howto_12 -6.13 "NEMD simulations"_#howto_13 -6.14 "Finite-size spherical and aspherical particles"_#howto_14 -6.15 "Output from LAMMPS (thermo, dumps, computes, fixes, variables)"_#howto_15 -6.16 "Thermostatting, barostatting and computing temperature"_#howto_16 -6.17 "Walls"_#howto_17 -6.18 "Elastic constants"_#howto_18 -6.19 "Library interface to LAMMPS"_#howto_19 -6.20 "Calculating thermal conductivity"_#howto_20 -6.21 "Calculating viscosity"_#howto_21 -6.22 "Calculating a diffusion coefficient"_#howto_22 -6.23 "Using chunks to calculate system properties"_#howto_23 -6.24 "Setting parameters for the kspace_style pppm/disp command"_#howto_24 -6.25 "Polarizable models"_#howto_25 -6.26 "Adiabatic core/shell model"_#howto_26 -6.27 "Drude induced dipoles"_#howto_27 -6.28 "Magnetic spins"_#howto_28 :all(b) - -The example input scripts included in the LAMMPS distribution and -highlighted on the "Examples"_Examples.html doc page also show how to -setup and run various kinds of simulations. - -:line -:line - -6.1 Restarting a simulation :link(howto_1),h4 - -There are 3 ways to continue a long LAMMPS simulation. Multiple -"run"_run.html commands can be used in the same input script. Each -run will continue from where the previous run left off. Or binary -restart files can be saved to disk using the "restart"_restart.html -command. At a later time, these binary files can be read via a -"read_restart"_read_restart.html command in a new script. Or they can -be converted to text data files using the "-r command-line -switch"_Section_start.html#start_6 and read by a -"read_data"_read_data.html command in a new script. - -Here we give examples of 2 scripts that read either a binary restart -file or a converted data file and then issue a new run command to -continue where the previous run left off. They illustrate what -settings must be made in the new script. Details are discussed in the -documentation for the "read_restart"_read_restart.html and -"read_data"_read_data.html commands. - -Look at the {in.chain} input script provided in the {bench} directory -of the LAMMPS distribution to see the original script that these 2 -scripts are based on. If that script had the line - -restart 50 tmp.restart :pre - -added to it, it would produce 2 binary restart files (tmp.restart.50 -and tmp.restart.100) as it ran. - -This script could be used to read the 1st restart file and re-run the -last 50 timesteps: - -read_restart tmp.restart.50 :pre - -neighbor 0.4 bin -neigh_modify every 1 delay 1 :pre - -fix 1 all nve -fix 2 all langevin 1.0 1.0 10.0 904297 :pre - -timestep 0.012 :pre - -run 50 :pre - -Note that the following commands do not need to be repeated because -their settings are included in the restart file: {units, atom_style, -special_bonds, pair_style, bond_style}. However these commands do -need to be used, since their settings are not in the restart file: -{neighbor, fix, timestep}. - -If you actually use this script to perform a restarted run, you will -notice that the thermodynamic data match at step 50 (if you also put a -"thermo 50" command in the original script), but do not match at step -100. This is because the "fix langevin"_fix_langevin.html command -uses random numbers in a way that does not allow for perfect restarts. - -As an alternate approach, the restart file could be converted to a data -file as follows: - -lmp_g++ -r tmp.restart.50 tmp.restart.data :pre - -Then, this script could be used to re-run the last 50 steps: - -units lj -atom_style bond -pair_style lj/cut 1.12 -pair_modify shift yes -bond_style fene -special_bonds 0.0 1.0 1.0 :pre - -read_data tmp.restart.data :pre - -neighbor 0.4 bin -neigh_modify every 1 delay 1 :pre - -fix 1 all nve -fix 2 all langevin 1.0 1.0 10.0 904297 :pre - -timestep 0.012 :pre - -reset_timestep 50 -run 50 :pre - -Note that nearly all the settings specified in the original {in.chain} -script must be repeated, except the {pair_coeff} and {bond_coeff} -commands since the new data file lists the force field coefficients. -Also, the "reset_timestep"_reset_timestep.html command is used to tell -LAMMPS the current timestep. This value is stored in restart files, -but not in data files. - -:line - -6.2 2d simulations :link(howto_2),h4 - -Use the "dimension"_dimension.html command to specify a 2d simulation. - -Make the simulation box periodic in z via the "boundary"_boundary.html -command. This is the default. - -If using the "create box"_create_box.html command to define a -simulation box, set the z dimensions narrow, but finite, so that the -create_atoms command will tile the 3d simulation box with a single z -plane of atoms - e.g. - -"create box"_create_box.html 1 -10 10 -10 10 -0.25 0.25 :pre - -If using the "read data"_read_data.html command to read in a file of -atom coordinates, set the "zlo zhi" values to be finite but narrow, -similar to the create_box command settings just described. For each -atom in the file, assign a z coordinate so it falls inside the -z-boundaries of the box - e.g. 0.0. - -Use the "fix enforce2d"_fix_enforce2d.html command as the last -defined fix to insure that the z-components of velocities and forces -are zeroed out every timestep. The reason to make it the last fix is -so that any forces induced by other fixes will be zeroed out. - -Many of the example input scripts included in the LAMMPS distribution -are for 2d models. - -NOTE: Some models in LAMMPS treat particles as finite-size spheres, as -opposed to point particles. See the "atom_style -sphere"_atom_style.html and "fix nve/sphere"_fix_nve_sphere.html -commands for details. By default, for 2d simulations, such particles -will still be modeled as 3d spheres, not 2d discs (circles), meaning -their moment of inertia will be that of a sphere. If you wish to -model them as 2d discs, see the "set density/disc"_set.html command -and the {disc} option for the "fix nve/sphere"_fix_nve_sphere.html, -"fix nvt/sphere"_fix_nvt_sphere.html, "fix -nph/sphere"_fix_nph_sphere.html, "fix npt/sphere"_fix_npt_sphere.html -commands. - -:line - -6.3 CHARMM, AMBER, and DREIDING force fields :link(howto_3),h4 - -A force field has 2 parts: the formulas that define it and the -coefficients used for a particular system. Here we only discuss -formulas implemented in LAMMPS that correspond to formulas commonly -used in the CHARMM, AMBER, and DREIDING force fields. Setting -coefficients is done in the input data file via the -"read_data"_read_data.html command or in the input script with -commands like "pair_coeff"_pair_coeff.html or -"bond_coeff"_bond_coeff.html. See the "Tools"_Tools.html doc page for -additional tools that can use CHARMM or AMBER to assign force field -coefficients and convert their output into LAMMPS input. - -See "(MacKerell)"_#howto-MacKerell for a description of the CHARMM force -field. See "(Cornell)"_#howto-Cornell for a description of the AMBER force -field. - -:link(charmm,http://www.scripps.edu/brooks) -:link(amber,http://amber.scripps.edu) - -These style choices compute force field formulas that are consistent -with common options in CHARMM or AMBER. See each command's -documentation for the formula it computes. - -"bond_style"_bond_harmonic.html harmonic -"angle_style"_angle_charmm.html charmm -"dihedral_style"_dihedral_charmm.html charmmfsh -"dihedral_style"_dihedral_charmm.html charmm -"pair_style"_pair_charmm.html lj/charmmfsw/coul/charmmfsh -"pair_style"_pair_charmm.html lj/charmmfsw/coul/long -"pair_style"_pair_charmm.html lj/charmm/coul/charmm -"pair_style"_pair_charmm.html lj/charmm/coul/charmm/implicit -"pair_style"_pair_charmm.html lj/charmm/coul/long :ul - -"special_bonds"_special_bonds.html charmm -"special_bonds"_special_bonds.html amber :ul - -NOTE: For CHARMM, newer {charmmfsw} or {charmmfsh} styles were -released in March 2017. We recommend they be used instead of the -older {charmm} styles. See discussion of the differences on the "pair -charmm"_pair_charmm.html and "dihedral charmm"_dihedral_charmm.html -doc pages. - -DREIDING is a generic force field developed by the "Goddard -group"_http://www.wag.caltech.edu at Caltech and is useful for -predicting structures and dynamics of organic, biological and -main-group inorganic molecules. The philosophy in DREIDING is to use -general force constants and geometry parameters based on simple -hybridization considerations, rather than individual force constants -and geometric parameters that depend on the particular combinations of -atoms involved in the bond, angle, or torsion terms. DREIDING has an -"explicit hydrogen bond term"_pair_hbond_dreiding.html to describe -interactions involving a hydrogen atom on very electronegative atoms -(N, O, F). - -See "(Mayo)"_#howto-Mayo for a description of the DREIDING force field - -These style choices compute force field formulas that are consistent -with the DREIDING force field. See each command's -documentation for the formula it computes. - -"bond_style"_bond_harmonic.html harmonic -"bond_style"_bond_morse.html morse :ul - -"angle_style"_angle_harmonic.html harmonic -"angle_style"_angle_cosine.html cosine -"angle_style"_angle_cosine_periodic.html cosine/periodic :ul - -"dihedral_style"_dihedral_charmm.html charmm -"improper_style"_improper_umbrella.html umbrella :ul - -"pair_style"_pair_buck.html buck -"pair_style"_pair_buck.html buck/coul/cut -"pair_style"_pair_buck.html buck/coul/long -"pair_style"_pair_lj.html lj/cut -"pair_style"_pair_lj.html lj/cut/coul/cut -"pair_style"_pair_lj.html lj/cut/coul/long :ul - -"pair_style"_pair_hbond_dreiding.html hbond/dreiding/lj -"pair_style"_pair_hbond_dreiding.html hbond/dreiding/morse :ul - -"special_bonds"_special_bonds.html dreiding :ul - -:line - -6.4 Running multiple simulations from one input script :link(howto_4),h4 - -This can be done in several ways. See the documentation for -individual commands for more details on how these examples work. - -If "multiple simulations" means continue a previous simulation for -more timesteps, then you simply use the "run"_run.html command -multiple times. For example, this script - -units lj -atom_style atomic -read_data data.lj -run 10000 -run 10000 -run 10000 -run 10000 -run 10000 :pre - -would run 5 successive simulations of the same system for a total of -50,000 timesteps. - -If you wish to run totally different simulations, one after the other, -the "clear"_clear.html command can be used in between them to -re-initialize LAMMPS. For example, this script - -units lj -atom_style atomic -read_data data.lj -run 10000 -clear -units lj -atom_style atomic -read_data data.lj.new -run 10000 :pre - -would run 2 independent simulations, one after the other. - -For large numbers of independent simulations, you can use -"variables"_variable.html and the "next"_next.html and -"jump"_jump.html commands to loop over the same input script -multiple times with different settings. For example, this -script, named in.polymer - -variable d index run1 run2 run3 run4 run5 run6 run7 run8 -shell cd $d -read_data data.polymer -run 10000 -shell cd .. -clear -next d -jump in.polymer :pre - -would run 8 simulations in different directories, using a data.polymer -file in each directory. The same concept could be used to run the -same system at 8 different temperatures, using a temperature variable -and storing the output in different log and dump files, for example - -variable a loop 8 -variable t index 0.8 0.85 0.9 0.95 1.0 1.05 1.1 1.15 -log log.$a -read data.polymer -velocity all create $t 352839 -fix 1 all nvt $t $t 100.0 -dump 1 all atom 1000 dump.$a -run 100000 -clear -next t -next a -jump in.polymer :pre - -All of the above examples work whether you are running on 1 or -multiple processors, but assumed you are running LAMMPS on a single -partition of processors. LAMMPS can be run on multiple partitions via -the "-partition" command-line switch as described in "this -section"_Section_start.html#start_6 of the manual. - -In the last 2 examples, if LAMMPS were run on 3 partitions, the same -scripts could be used if the "index" and "loop" variables were -replaced with {universe}-style variables, as described in the -"variable"_variable.html command. Also, the "next t" and "next a" -commands would need to be replaced with a single "next a t" command. -With these modifications, the 8 simulations of each script would run -on the 3 partitions one after the other until all were finished. -Initially, 3 simulations would be started simultaneously, one on each -partition. When one finished, that partition would then start -the 4th simulation, and so forth, until all 8 were completed. - -:line - -6.5 Multi-replica simulations :link(howto_5),h4 - -Several commands in LAMMPS run mutli-replica simulations, meaning -that multiple instances (replicas) of your simulation are run -simultaneously, with small amounts of data exchanged between replicas -periodically. - -These are the relevant commands: - -"neb"_neb.html for nudged elastic band calculations -"prd"_prd.html for parallel replica dynamics -"tad"_tad.html for temperature accelerated dynamics -"temper"_temper.html for parallel tempering -"fix pimd"_fix_pimd.html for path-integral molecular dynamics (PIMD) :ul - -NEB is a method for finding transition states and barrier energies. -PRD and TAD are methods for performing accelerated dynamics to find -and perform infrequent events. Parallel tempering or replica exchange -runs different replicas at a series of temperature to facilitate -rare-event sampling. - -These commands can only be used if LAMMPS was built with the REPLICA -package. See the "Making LAMMPS"_Section_start.html#start_3 section -for more info on packages. - -PIMD runs different replicas whose individual particles are coupled -together by springs to model a system or ring-polymers. - -This commands can only be used if LAMMPS was built with the USER-MISC -package. See the "Making LAMMPS"_Section_start.html#start_3 section -for more info on packages. - -In all these cases, you must run with one or more processors per -replica. The processors assigned to each replica are determined at -run-time by using the "-partition command-line -switch"_Section_start.html#start_6 to launch LAMMPS on multiple -partitions, which in this context are the same as replicas. E.g. -these commands: - -mpirun -np 16 lmp_linux -partition 8x2 -in in.temper -mpirun -np 8 lmp_linux -partition 8x1 -in in.neb :pre - -would each run 8 replicas, on either 16 or 8 processors. Note the use -of the "-in command-line switch"_Section_start.html#start_6 to specify -the input script which is required when running in multi-replica mode. - -Also note that with MPI installed on a machine (e.g. your desktop), -you can run on more (virtual) processors than you have physical -processors. Thus the above commands could be run on a -single-processor (or few-processor) desktop so that you can run -a multi-replica simulation on more replicas than you have -physical processors. - -:line - -6.6 Granular models :link(howto_6),h4 - -Granular system are composed of spherical particles with a diameter, -as opposed to point particles. This means they have an angular -velocity and torque can be imparted to them to cause them to rotate. - -To run a simulation of a granular model, you will want to use -the following commands: - -"atom_style sphere"_atom_style.html -"fix nve/sphere"_fix_nve_sphere.html -"fix gravity"_fix_gravity.html :ul - -This compute - -"compute erotate/sphere"_compute_erotate_sphere.html :ul - -calculates rotational kinetic energy which can be "output with -thermodynamic info"_Section_howto.html#howto_15. - -Use one of these 3 pair potentials, which compute forces and torques -between interacting pairs of particles: - -"pair_style"_pair_style.html gran/history -"pair_style"_pair_style.html gran/no_history -"pair_style"_pair_style.html gran/hertzian :ul - -These commands implement fix options specific to granular systems: - -"fix freeze"_fix_freeze.html -"fix pour"_fix_pour.html -"fix viscous"_fix_viscous.html -"fix wall/gran"_fix_wall_gran.html :ul - -The fix style {freeze} zeroes both the force and torque of frozen -atoms, and should be used for granular system instead of the fix style -{setforce}. - -For computational efficiency, you can eliminate needless pairwise -computations between frozen atoms by using this command: - -"neigh_modify"_neigh_modify.html exclude :ul - -NOTE: By default, for 2d systems, granular particles are still modeled -as 3d spheres, not 2d discs (circles), meaning their moment of inertia -will be the same as in 3d. If you wish to model granular particles in -2d as 2d discs, see the note on this topic in "Section -6.2"_Section_howto.html#howto_2, where 2d simulations are discussed. - -:line - -6.7 TIP3P water model :link(howto_7),h4 - -The TIP3P water model as implemented in CHARMM -"(MacKerell)"_#howto-MacKerell specifies a 3-site rigid water molecule with -charges and Lennard-Jones parameters assigned to each of the 3 atoms. -In LAMMPS the "fix shake"_fix_shake.html command can be used to hold -the two O-H bonds and the H-O-H angle rigid. A bond style of -{harmonic} and an angle style of {harmonic} or {charmm} should also be -used. - -These are the additional parameters (in real units) to set for O and H -atoms and the water molecule to run a rigid TIP3P-CHARMM model with a -cutoff. The K values can be used if a flexible TIP3P model (without -fix shake) is desired. If the LJ epsilon and sigma for HH and OH are -set to 0.0, it corresponds to the original 1983 TIP3P model -"(Jorgensen)"_#Jorgensen1. - -O mass = 15.9994 -H mass = 1.008 -O charge = -0.834 -H charge = 0.417 -LJ epsilon of OO = 0.1521 -LJ sigma of OO = 3.1507 -LJ epsilon of HH = 0.0460 -LJ sigma of HH = 0.4000 -LJ epsilon of OH = 0.0836 -LJ sigma of OH = 1.7753 -K of OH bond = 450 -r0 of OH bond = 0.9572 -K of HOH angle = 55 -theta of HOH angle = 104.52 :all(b),p - -These are the parameters to use for TIP3P with a long-range Coulombic -solver (e.g. Ewald or PPPM in LAMMPS), see "(Price)"_#Price1 for -details: - -O mass = 15.9994 -H mass = 1.008 -O charge = -0.830 -H charge = 0.415 -LJ epsilon of OO = 0.102 -LJ sigma of OO = 3.188 -LJ epsilon, sigma of OH, HH = 0.0 -K of OH bond = 450 -r0 of OH bond = 0.9572 -K of HOH angle = 55 -theta of HOH angle = 104.52 :all(b),p - -Wikipedia also has a nice article on "water -models"_http://en.wikipedia.org/wiki/Water_model. - -:line - -6.8 TIP4P water model :link(howto_8),h4 - -The four-point TIP4P rigid water model extends the traditional -three-point TIP3P model by adding an additional site, usually -massless, where the charge associated with the oxygen atom is placed. -This site M is located at a fixed distance away from the oxygen along -the bisector of the HOH bond angle. A bond style of {harmonic} and an -angle style of {harmonic} or {charmm} should also be used. - -A TIP4P model is run with LAMMPS using either this command -for a cutoff model: - -"pair_style lj/cut/tip4p/cut"_pair_lj.html - -or these two commands for a long-range model: - -"pair_style lj/cut/tip4p/long"_pair_lj.html -"kspace_style pppm/tip4p"_kspace_style.html :ul - -For both models, the bond lengths and bond angles should be held fixed -using the "fix shake"_fix_shake.html command. - -These are the additional parameters (in real units) to set for O and H -atoms and the water molecule to run a rigid TIP4P model with a cutoff -"(Jorgensen)"_#Jorgensen1. Note that the OM distance is specified in -the "pair_style"_pair_style.html command, not as part of the pair -coefficients. - -O mass = 15.9994 -H mass = 1.008 -O charge = -1.040 -H charge = 0.520 -r0 of OH bond = 0.9572 -theta of HOH angle = 104.52 -OM distance = 0.15 -LJ epsilon of O-O = 0.1550 -LJ sigma of O-O = 3.1536 -LJ epsilon, sigma of OH, HH = 0.0 -Coulombic cutoff = 8.5 :all(b),p - -For the TIP4/Ice model (J Chem Phys, 122, 234511 (2005); -http://dx.doi.org/10.1063/1.1931662) these values can be used: - -O mass = 15.9994 -H mass = 1.008 -O charge = -1.1794 -H charge = 0.5897 -r0 of OH bond = 0.9572 -theta of HOH angle = 104.52 -OM distance = 0.1577 -LJ epsilon of O-O = 0.21084 -LJ sigma of O-O = 3.1668 -LJ epsilon, sigma of OH, HH = 0.0 -Coulombic cutoff = 8.5 :all(b),p - -For the TIP4P/2005 model (J Chem Phys, 123, 234505 (2005); -http://dx.doi.org/10.1063/1.2121687), these values can be used: - -O mass = 15.9994 -H mass = 1.008 -O charge = -1.1128 -H charge = 0.5564 -r0 of OH bond = 0.9572 -theta of HOH angle = 104.52 -OM distance = 0.1546 -LJ epsilon of O-O = 0.1852 -LJ sigma of O-O = 3.1589 -LJ epsilon, sigma of OH, HH = 0.0 -Coulombic cutoff = 8.5 :all(b),p - -These are the parameters to use for TIP4P with a long-range Coulombic -solver (e.g. Ewald or PPPM in LAMMPS): - -O mass = 15.9994 -H mass = 1.008 -O charge = -1.0484 -H charge = 0.5242 -r0 of OH bond = 0.9572 -theta of HOH angle = 104.52 -OM distance = 0.1250 -LJ epsilon of O-O = 0.16275 -LJ sigma of O-O = 3.16435 -LJ epsilon, sigma of OH, HH = 0.0 :all(b),p - -Note that the when using the TIP4P pair style, the neighbor list -cutoff for Coulomb interactions is effectively extended by a distance -2 * (OM distance), to account for the offset distance of the -fictitious charges on O atoms in water molecules. Thus it is -typically best in an efficiency sense to use a LJ cutoff >= Coulomb -cutoff + 2*(OM distance), to shrink the size of the neighbor list. -This leads to slightly larger cost for the long-range calculation, so -you can test the trade-off for your model. The OM distance and the LJ -and Coulombic cutoffs are set in the "pair_style -lj/cut/tip4p/long"_pair_lj.html command. - -Wikipedia also has a nice article on "water -models"_http://en.wikipedia.org/wiki/Water_model. - -:line - -6.9 SPC water model :link(howto_9),h4 - -The SPC water model specifies a 3-site rigid water molecule with -charges and Lennard-Jones parameters assigned to each of the 3 atoms. -In LAMMPS the "fix shake"_fix_shake.html command can be used to hold -the two O-H bonds and the H-O-H angle rigid. A bond style of -{harmonic} and an angle style of {harmonic} or {charmm} should also be -used. - -These are the additional parameters (in real units) to set for O and H -atoms and the water molecule to run a rigid SPC model. - -O mass = 15.9994 -H mass = 1.008 -O charge = -0.820 -H charge = 0.410 -LJ epsilon of OO = 0.1553 -LJ sigma of OO = 3.166 -LJ epsilon, sigma of OH, HH = 0.0 -r0 of OH bond = 1.0 -theta of HOH angle = 109.47 :all(b),p - -Note that as originally proposed, the SPC model was run with a 9 -Angstrom cutoff for both LJ and Coulommbic terms. It can also be used -with long-range Coulombics (Ewald or PPPM in LAMMPS), without changing -any of the parameters above, though it becomes a different model in -that mode of usage. - -The SPC/E (extended) water model is the same, except -the partial charge assignments change: - -O charge = -0.8476 -H charge = 0.4238 :all(b),p - -See the "(Berendsen)"_#howto-Berendsen reference for more details on both -the SPC and SPC/E models. - -Wikipedia also has a nice article on "water -models"_http://en.wikipedia.org/wiki/Water_model. - -:line - -6.10 Coupling LAMMPS to other codes :link(howto_10),h4 - -LAMMPS is designed to allow it to be coupled to other codes. For -example, a quantum mechanics code might compute forces on a subset of -atoms and pass those forces to LAMMPS. Or a continuum finite element -(FE) simulation might use atom positions as boundary conditions on FE -nodal points, compute a FE solution, and return interpolated forces on -MD atoms. - -LAMMPS can be coupled to other codes in at least 3 ways. Each has -advantages and disadvantages, which you'll have to think about in the -context of your application. - -(1) Define a new "fix"_fix.html command that calls the other code. In -this scenario, LAMMPS is the driver code. During its timestepping, -the fix is invoked, and can make library calls to the other code, -which has been linked to LAMMPS as a library. This is the way the -"POEMS"_poems package that performs constrained rigid-body motion on -groups of atoms is hooked to LAMMPS. See the "fix -poems"_fix_poems.html command for more details. See the -"Modify"_Modify.html doc page for info on how to add a new fix to -LAMMPS. - -:link(poems,http://www.rpi.edu/~anderk5/lab) - -(2) Define a new LAMMPS command that calls the other code. This is -conceptually similar to method (1), but in this case LAMMPS and the -other code are on a more equal footing. Note that now the other code -is not called during the timestepping of a LAMMPS run, but between -runs. The LAMMPS input script can be used to alternate LAMMPS runs -with calls to the other code, invoked via the new command. The -"run"_run.html command facilitates this with its {every} option, which -makes it easy to run a few steps, invoke the command, run a few steps, -invoke the command, etc. - -In this scenario, the other code can be called as a library, as in -(1), or it could be a stand-alone code, invoked by a system() call -made by the command (assuming your parallel machine allows one or more -processors to start up another program). In the latter case the -stand-alone code could communicate with LAMMPS thru files that the -command writes and reads. - -See the "Modify"_Modify.html doc page for how to add a new command to -LAMMPS. - -(3) Use LAMMPS as a library called by another code. In this case the -other code is the driver and calls LAMMPS as needed. Or a wrapper -code could link and call both LAMMPS and another code as libraries. -Again, the "run"_run.html command has options that allow it to be -invoked with minimal overhead (no setup or clean-up) if you wish to do -multiple short runs, driven by another program. - -Examples of driver codes that call LAMMPS as a library are included in -the examples/COUPLE directory of the LAMMPS distribution; see -examples/COUPLE/README for more details: - -simple: simple driver programs in C++ and C which invoke LAMMPS as a -library :ulb,l - -lammps_quest: coupling of LAMMPS and "Quest"_quest, to run classical -MD with quantum forces calculated by a density functional code :l - -lammps_spparks: coupling of LAMMPS and "SPPARKS"_spparks, to couple -a kinetic Monte Carlo model for grain growth using MD to calculate -strain induced across grain boundaries :l -:ule - -:link(quest,http://dft.sandia.gov/Quest) -:link(spparks,http://www.sandia.gov/~sjplimp/spparks.html) - -"This section"_Section_start.html#start_5 of the documentation -describes how to build LAMMPS as a library. Once this is done, you -can interface with LAMMPS either via C++, C, Fortran, or Python (or -any other language that supports a vanilla C-like interface). For -example, from C++ you could create one (or more) "instances" of -LAMMPS, pass it an input script to process, or execute individual -commands, all by invoking the correct class methods in LAMMPS. From C -or Fortran you can make function calls to do the same things. See the -"Python"_Python.html doc page for a description of the Python wrapper -provided with LAMMPS that operates through the LAMMPS library -interface. - -The files src/library.cpp and library.h contain the C-style interface -to LAMMPS. See "Section 6.19"_Section_howto.html#howto_19 of the -manual for a description of the interface and how to extend it for -your needs. - -Note that the lammps_open() function that creates an instance of -LAMMPS takes an MPI communicator as an argument. This means that -instance of LAMMPS will run on the set of processors in the -communicator. Thus the calling code can run LAMMPS on all or a subset -of processors. For example, a wrapper script might decide to -alternate between LAMMPS and another code, allowing them both to run -on all the processors. Or it might allocate half the processors to -LAMMPS and half to the other code and run both codes simultaneously -before syncing them up periodically. Or it might instantiate multiple -instances of LAMMPS to perform different calculations. - -:line - -6.11 Visualizing LAMMPS snapshots :link(howto_11),h4 - -LAMMPS itself does not do visualization, but snapshots from LAMMPS -simulations can be visualized (and analyzed) in a variety of ways. - -LAMMPS snapshots are created by the "dump"_dump.html command which can -create files in several formats. The native LAMMPS dump format is a -text file (see "dump atom" or "dump custom") which can be visualized -by several popular visualization tools. The "dump -image"_dump_image.html and "dump movie"_dump_image.html styles can -output internally rendered images and convert a sequence of them to a -movie during the MD run. Several programs included with LAMMPS as -auxiliary tools can convert between LAMMPS format files and other -formats. See the "Tools"_Tools.html doc page for details. - -A Python-based toolkit distributed by our group can read native LAMMPS -dump files, including custom dump files with additional columns of -user-specified atom information, and convert them to various formats -or pipe them into visualization software directly. See the "Pizza.py -WWW site"_pizza for details. Specifically, Pizza.py can convert -LAMMPS dump files into PDB, XYZ, "Ensight"_ensight, and VTK formats. -Pizza.py can pipe LAMMPS dump files directly into the Raster3d and -RasMol visualization programs. Pizza.py has tools that do interactive -3d OpenGL visualization and one that creates SVG images of dump file -snapshots. - -:link(pizza,http://www.sandia.gov/~sjplimp/pizza.html) -:link(ensight,http://www.ensight.com) -:link(atomeye,http://mt.seas.upenn.edu/Archive/Graphics/A) - -:line - -6.12 Triclinic (non-orthogonal) simulation boxes :link(howto_12),h4 - -By default, LAMMPS uses an orthogonal simulation box to encompass the -particles. The "boundary"_boundary.html command sets the boundary -conditions of the box (periodic, non-periodic, etc). The orthogonal -box has its "origin" at (xlo,ylo,zlo) and is defined by 3 edge vectors -starting from the origin given by [a] = (xhi-xlo,0,0); [b] = -(0,yhi-ylo,0); [c] = (0,0,zhi-zlo). The 6 parameters -(xlo,xhi,ylo,yhi,zlo,zhi) are defined at the time the simulation box -is created, e.g. by the "create_box"_create_box.html or -"read_data"_read_data.html or "read_restart"_read_restart.html -commands. Additionally, LAMMPS defines box size parameters lx,ly,lz -where lx = xhi-xlo, and similarly in the y and z dimensions. The 6 -parameters, as well as lx,ly,lz, can be output via the "thermo_style -custom"_thermo_style.html command. - -LAMMPS also allows simulations to be performed in triclinic -(non-orthogonal) simulation boxes shaped as a parallelepiped with -triclinic symmetry. The parallelepiped has its "origin" at -(xlo,ylo,zlo) and is defined by 3 edge vectors starting from the -origin given by [a] = (xhi-xlo,0,0); [b] = (xy,yhi-ylo,0); [c] = -(xz,yz,zhi-zlo). {xy,xz,yz} can be 0.0 or positive or negative values -and are called "tilt factors" because they are the amount of -displacement applied to faces of an originally orthogonal box to -transform it into the parallelepiped. In LAMMPS the triclinic -simulation box edge vectors [a], [b], and [c] cannot be arbitrary -vectors. As indicated, [a] must lie on the positive x axis. [b] must -lie in the xy plane, with strictly positive y component. [c] may have -any orientation with strictly positive z component. The requirement -that [a], [b], and [c] have strictly positive x, y, and z components, -respectively, ensures that [a], [b], and [c] form a complete -right-handed basis. These restrictions impose no loss of generality, -since it is possible to rotate/invert any set of 3 crystal basis -vectors so that they conform to the restrictions. - -For example, assume that the 3 vectors [A],[B],[C] are the edge -vectors of a general parallelepiped, where there is no restriction on -[A],[B],[C] other than they form a complete right-handed basis i.e. -[A] x [B] . [C] > 0. The equivalent LAMMPS [a],[b],[c] are a linear -rotation of [A], [B], and [C] and can be computed as follows: - -:c,image(Eqs/transform.jpg) - -where A = | [A] | indicates the scalar length of [A]. The hat symbol (^) -indicates the corresponding unit vector. {beta} and {gamma} are angles -between the vectors described below. Note that by construction, -[a], [b], and [c] have strictly positive x, y, and z components, respectively. -If it should happen that -[A], [B], and [C] form a left-handed basis, then the above equations -are not valid for [c]. In this case, it is necessary -to first apply an inversion. This can be achieved -by interchanging two basis vectors or by changing the sign of one of them. - -For consistency, the same rotation/inversion applied to the basis vectors -must also be applied to atom positions, velocities, -and any other vector quantities. -This can be conveniently achieved by first converting to -fractional coordinates in the -old basis and then converting to distance coordinates in the new basis. -The transformation is given by the following equation: - -:c,image(Eqs/rotate.jpg) - -where {V} is the volume of the box, [X] is the original vector quantity and -[x] is the vector in the LAMMPS basis. - -There is no requirement that a triclinic box be periodic in any -dimension, though it typically should be in at least the 2nd dimension -of the tilt (y in xy) if you want to enforce a shift in periodic -boundary conditions across that boundary. Some commands that work -with triclinic boxes, e.g. the "fix deform"_fix_deform.html and "fix -npt"_fix_nh.html commands, require periodicity or non-shrink-wrap -boundary conditions in specific dimensions. See the command doc pages -for details. - -The 9 parameters (xlo,xhi,ylo,yhi,zlo,zhi,xy,xz,yz) are defined at the -time the simulation box is created. This happens in one of 3 ways. -If the "create_box"_create_box.html command is used with a region of -style {prism}, then a triclinic box is setup. See the -"region"_region.html command for details. If the -"read_data"_read_data.html command is used to define the simulation -box, and the header of the data file contains a line with the "xy xz -yz" keyword, then a triclinic box is setup. See the -"read_data"_read_data.html command for details. Finally, if the -"read_restart"_read_restart.html command reads a restart file which -was written from a simulation using a triclinic box, then a triclinic -box will be setup for the restarted simulation. - -Note that you can define a triclinic box with all 3 tilt factors = -0.0, so that it is initially orthogonal. This is necessary if the box -will become non-orthogonal, e.g. due to the "fix npt"_fix_nh.html or -"fix deform"_fix_deform.html commands. Alternatively, you can use the -"change_box"_change_box.html command to convert a simulation box from -orthogonal to triclinic and vice versa. - -As with orthogonal boxes, LAMMPS defines triclinic box size parameters -lx,ly,lz where lx = xhi-xlo, and similarly in the y and z dimensions. -The 9 parameters, as well as lx,ly,lz, can be output via the -"thermo_style custom"_thermo_style.html command. - -To avoid extremely tilted boxes (which would be computationally -inefficient), LAMMPS normally requires that no tilt factor can skew -the box more than half the distance of the parallel box length, which -is the 1st dimension in the tilt factor (x for xz). This is required -both when the simulation box is created, e.g. via the -"create_box"_create_box.html or "read_data"_read_data.html commands, -as well as when the box shape changes dynamically during a simulation, -e.g. via the "fix deform"_fix_deform.html or "fix npt"_fix_nh.html -commands. - -For example, if xlo = 2 and xhi = 12, then the x box length is 10 and -the xy tilt factor must be between -5 and 5. Similarly, both xz and -yz must be between -(xhi-xlo)/2 and +(yhi-ylo)/2. Note that this is -not a limitation, since if the maximum tilt factor is 5 (as in this -example), then configurations with tilt = ..., -15, -5, 5, 15, 25, -... are geometrically all equivalent. If the box tilt exceeds this -limit during a dynamics run (e.g. via the "fix deform"_fix_deform.html -command), then the box is "flipped" to an equivalent shape with a tilt -factor within the bounds, so the run can continue. See the "fix -deform"_fix_deform.html doc page for further details. - -One exception to this rule is if the 1st dimension in the tilt -factor (x for xy) is non-periodic. In that case, the limits on the -tilt factor are not enforced, since flipping the box in that dimension -does not change the atom positions due to non-periodicity. In this -mode, if you tilt the system to extreme angles, the simulation will -simply become inefficient, due to the highly skewed simulation box. - -The limitation on not creating a simulation box with a tilt factor -skewing the box more than half the distance of the parallel box length -can be overridden via the "box"_box.html command. Setting the {tilt} -keyword to {large} allows any tilt factors to be specified. - -Box flips that may occur using the "fix deform"_fix_deform.html or -"fix npt"_fix_nh.html commands can be turned off using the {flip no} -option with either of the commands. - -Note that if a simulation box has a large tilt factor, LAMMPS will run -less efficiently, due to the large volume of communication needed to -acquire ghost atoms around a processor's irregular-shaped sub-domain. -For extreme values of tilt, LAMMPS may also lose atoms and generate an -error. - -Triclinic crystal structures are often defined using three lattice -constants {a}, {b}, and {c}, and three angles {alpha}, {beta} and -{gamma}. Note that in this nomenclature, the a, b, and c lattice -constants are the scalar lengths of the edge vectors [a], [b], and [c] -defined above. The relationship between these 6 quantities -(a,b,c,alpha,beta,gamma) and the LAMMPS box sizes (lx,ly,lz) = -(xhi-xlo,yhi-ylo,zhi-zlo) and tilt factors (xy,xz,yz) is as follows: - -:c,image(Eqs/box.jpg) - -The inverse relationship can be written as follows: - -:c,image(Eqs/box_inverse.jpg) - -The values of {a}, {b}, {c} , {alpha}, {beta} , and {gamma} can be printed -out or accessed by computes using the -"thermo_style custom"_thermo_style.html keywords -{cella}, {cellb}, {cellc}, {cellalpha}, {cellbeta}, {cellgamma}, -respectively. - -As discussed on the "dump"_dump.html command doc page, when the BOX -BOUNDS for a snapshot is written to a dump file for a triclinic box, -an orthogonal bounding box which encloses the triclinic simulation box -is output, along with the 3 tilt factors (xy, xz, yz) of the triclinic -box, formatted as follows: - -ITEM: BOX BOUNDS xy xz yz -xlo_bound xhi_bound xy -ylo_bound yhi_bound xz -zlo_bound zhi_bound yz :pre - -This bounding box is convenient for many visualization programs and is -calculated from the 9 triclinic box parameters -(xlo,xhi,ylo,yhi,zlo,zhi,xy,xz,yz) as follows: - -xlo_bound = xlo + MIN(0.0,xy,xz,xy+xz) -xhi_bound = xhi + MAX(0.0,xy,xz,xy+xz) -ylo_bound = ylo + MIN(0.0,yz) -yhi_bound = yhi + MAX(0.0,yz) -zlo_bound = zlo -zhi_bound = zhi :pre - -These formulas can be inverted if you need to convert the bounding box -back into the triclinic box parameters, e.g. xlo = xlo_bound - -MIN(0.0,xy,xz,xy+xz). - -One use of triclinic simulation boxes is to model solid-state crystals -with triclinic symmetry. The "lattice"_lattice.html command can be -used with non-orthogonal basis vectors to define a lattice that will -tile a triclinic simulation box via the -"create_atoms"_create_atoms.html command. - -A second use is to run Parinello-Rahman dynamics via the "fix -npt"_fix_nh.html command, which will adjust the xy, xz, yz tilt -factors to compensate for off-diagonal components of the pressure -tensor. The analog for an "energy minimization"_minimize.html is -the "fix box/relax"_fix_box_relax.html command. - -A third use is to shear a bulk solid to study the response of the -material. The "fix deform"_fix_deform.html command can be used for -this purpose. It allows dynamic control of the xy, xz, yz tilt -factors as a simulation runs. This is discussed in the next section -on non-equilibrium MD (NEMD) simulations. - -:line - -6.13 NEMD simulations :link(howto_13),h4 - -Non-equilibrium molecular dynamics or NEMD simulations are typically -used to measure a fluid's rheological properties such as viscosity. -In LAMMPS, such simulations can be performed by first setting up a -non-orthogonal simulation box (see the preceding Howto section). - -A shear strain can be applied to the simulation box at a desired -strain rate by using the "fix deform"_fix_deform.html command. The -"fix nvt/sllod"_fix_nvt_sllod.html command can be used to thermostat -the sheared fluid and integrate the SLLOD equations of motion for the -system. Fix nvt/sllod uses "compute -temp/deform"_compute_temp_deform.html to compute a thermal temperature -by subtracting out the streaming velocity of the shearing atoms. The -velocity profile or other properties of the fluid can be monitored via -the "fix ave/chunk"_fix_ave_chunk.html command. - -As discussed in the previous section on non-orthogonal simulation -boxes, the amount of tilt or skew that can be applied is limited by -LAMMPS for computational efficiency to be 1/2 of the parallel box -length. However, "fix deform"_fix_deform.html can continuously strain -a box by an arbitrary amount. As discussed in the "fix -deform"_fix_deform.html command, when the tilt value reaches a limit, -the box is flipped to the opposite limit which is an equivalent tiling -of periodic space. The strain rate can then continue to change as -before. In a long NEMD simulation these box re-shaping events may -occur many times. - -In a NEMD simulation, the "remap" option of "fix -deform"_fix_deform.html should be set to "remap v", since that is what -"fix nvt/sllod"_fix_nvt_sllod.html assumes to generate a velocity -profile consistent with the applied shear strain rate. - -An alternative method for calculating viscosities is provided via the -"fix viscosity"_fix_viscosity.html command. - -NEMD simulations can also be used to measure transport properties of a fluid -through a pore or channel. Simulations of steady-state flow can be performed -using the "fix flow/gauss"_fix_flow_gauss.html command. - -:line - -6.14 Finite-size spherical and aspherical particles :link(howto_14),h4 - -Typical MD models treat atoms or particles as point masses. Sometimes -it is desirable to have a model with finite-size particles such as -spheroids or ellipsoids or generalized aspherical bodies. The -difference is that such particles have a moment of inertia, rotational -energy, and angular momentum. Rotation is induced by torque coming -from interactions with other particles. - -LAMMPS has several options for running simulations with these kinds of -particles. The following aspects are discussed in turn: - -atom styles -pair potentials -time integration -computes, thermodynamics, and dump output -rigid bodies composed of finite-size particles :ul - -Example input scripts for these kinds of models are in the body, -colloid, dipole, ellipse, line, peri, pour, and tri directories of the -"examples directory"_Examples.html in the LAMMPS distribution. - -Atom styles :h4 - -There are several "atom styles"_atom_style.html that allow for -definition of finite-size particles: sphere, dipole, ellipsoid, line, -tri, peri, and body. - -The sphere style defines particles that are spheriods and each -particle can have a unique diameter and mass (or density). These -particles store an angular velocity (omega) and can be acted upon by -torque. The "set" command can be used to modify the diameter and mass -of individual particles, after then are created. - -The dipole style does not actually define finite-size particles, but -is often used in conjunction with spherical particles, via a command -like - -atom_style hybrid sphere dipole :pre - -This is because when dipoles interact with each other, they induce -torques, and a particle must be finite-size (i.e. have a moment of -inertia) in order to respond and rotate. See the "atom_style -dipole"_atom_style.html command for details. The "set" command can be -used to modify the orientation and length of the dipole moment of -individual particles, after then are created. - -The ellipsoid style defines particles that are ellipsoids and thus can -be aspherical. Each particle has a shape, specified by 3 diameters, -and mass (or density). These particles store an angular momentum and -their orientation (quaternion), and can be acted upon by torque. They -do not store an angular velocity (omega), which can be in a different -direction than angular momentum, rather they compute it as needed. -The "set" command can be used to modify the diameter, orientation, and -mass of individual particles, after then are created. It also has a -brief explanation of what quaternions are. - -The line style defines line segment particles with two end points and -a mass (or density). They can be used in 2d simulations, and they can -be joined together to form rigid bodies which represent arbitrary -polygons. - -The tri style defines triangular particles with three corner points -and a mass (or density). They can be used in 3d simulations, and they -can be joined together to form rigid bodies which represent arbitrary -particles with a triangulated surface. - -The peri style is used with "Peridynamic models"_pair_peri.html and -defines particles as having a volume, that is used internally in the -"pair_style peri"_pair_peri.html potentials. - -The body style allows for definition of particles which can represent -complex entities, such as surface meshes of discrete points, -collections of sub-particles, deformable objects, etc. The body style -is discussed in more detail on the "body"_body.html doc page. - -Note that if one of these atom styles is used (or multiple styles via -the "atom_style hybrid"_atom_style.html command), not all particles in -the system are required to be finite-size or aspherical. - -For example, in the ellipsoid style, if the 3 shape parameters are set -to the same value, the particle will be a sphere rather than an -ellipsoid. If the 3 shape parameters are all set to 0.0 or if the -diameter is set to 0.0, it will be a point particle. In the line or -tri style, if the lineflag or triflag is specified as 0, then it -will be a point particle. - -Some of the pair styles used to compute pairwise interactions between -finite-size particles also compute the correct interaction with point -particles as well, e.g. the interaction between a point particle and a -finite-size particle or between two point particles. If necessary, -"pair_style hybrid"_pair_hybrid.html can be used to insure the correct -interactions are computed for the appropriate style of interactions. -Likewise, using groups to partition particles (ellipsoids versus -spheres versus point particles) will allow you to use the appropriate -time integrators and temperature computations for each class of -particles. See the doc pages for various commands for details. - -Also note that for "2d simulations"_dimension.html, atom styles sphere -and ellipsoid still use 3d particles, rather than as circular disks or -ellipses. This means they have the same moment of inertia as the 3d -object. When temperature is computed, the correct degrees of freedom -are used for rotation in a 2d versus 3d system. - -Pair potentials :h4 - -When a system with finite-size particles is defined, the particles -will only rotate and experience torque if the force field computes -such interactions. These are the various "pair -styles"_pair_style.html that generate torque: - -"pair_style gran/history"_pair_gran.html -"pair_style gran/hertzian"_pair_gran.html -"pair_style gran/no_history"_pair_gran.html -"pair_style dipole/cut"_pair_dipole.html -"pair_style gayberne"_pair_gayberne.html -"pair_style resquared"_pair_resquared.html -"pair_style brownian"_pair_brownian.html -"pair_style lubricate"_pair_lubricate.html -"pair_style line/lj"_pair_line_lj.html -"pair_style tri/lj"_pair_tri_lj.html -"pair_style body"_pair_body.html :ul - -The granular pair styles are used with spherical particles. The -dipole pair style is used with the dipole atom style, which could be -applied to spherical or ellipsoidal particles. The GayBerne and -REsquared potentials require ellipsoidal particles, though they will -also work if the 3 shape parameters are the same (a sphere). The -Brownian and lubrication potentials are used with spherical particles. -The line, tri, and body potentials are used with line segment, -triangular, and body particles respectively. - -Time integration :h4 - -There are several fixes that perform time integration on finite-size -spherical particles, meaning the integrators update the rotational -orientation and angular velocity or angular momentum of the particles: - -"fix nve/sphere"_fix_nve_sphere.html -"fix nvt/sphere"_fix_nvt_sphere.html -"fix npt/sphere"_fix_npt_sphere.html :ul - -Likewise, there are 3 fixes that perform time integration on -ellipsoidal particles: - -"fix nve/asphere"_fix_nve_asphere.html -"fix nvt/asphere"_fix_nvt_asphere.html -"fix npt/asphere"_fix_npt_asphere.html :ul - -The advantage of these fixes is that those which thermostat the -particles include the rotational degrees of freedom in the temperature -calculation and thermostatting. The "fix langevin"_fix_langevin -command can also be used with its {omgea} or {angmom} options to -thermostat the rotational degrees of freedom for spherical or -ellipsoidal particles. Other thermostatting fixes only operate on the -translational kinetic energy of finite-size particles. - -These fixes perform constant NVE time integration on line segment, -triangular, and body particles: - -"fix nve/line"_fix_nve_line.html -"fix nve/tri"_fix_nve_tri.html -"fix nve/body"_fix_nve_body.html :ul - -Note that for mixtures of point and finite-size particles, these -integration fixes can only be used with "groups"_group.html which -contain finite-size particles. - -Computes, thermodynamics, and dump output :h4 - -There are several computes that calculate the temperature or -rotational energy of spherical or ellipsoidal particles: - -"compute temp/sphere"_compute_temp_sphere.html -"compute temp/asphere"_compute_temp_asphere.html -"compute erotate/sphere"_compute_erotate_sphere.html -"compute erotate/asphere"_compute_erotate_asphere.html :ul - -These include rotational degrees of freedom in their computation. If -you wish the thermodynamic output of temperature or pressure to use -one of these computes (e.g. for a system entirely composed of -finite-size particles), then the compute can be defined and the -"thermo_modify"_thermo_modify.html command used. Note that by default -thermodynamic quantities will be calculated with a temperature that -only includes translational degrees of freedom. See the -"thermo_style"_thermo_style.html command for details. - -These commands can be used to output various attributes of finite-size -particles: - -"dump custom"_dump.html -"compute property/atom"_compute_property_atom.html -"dump local"_dump.html -"compute body/local"_compute_body_local.html :ul - -Attributes include the dipole moment, the angular velocity, the -angular momentum, the quaternion, the torque, the end-point and -corner-point coordinates (for line and tri particles), and -sub-particle attributes of body particles. - -Rigid bodies composed of finite-size particles :h4 - -The "fix rigid"_fix_rigid.html command treats a collection of -particles as a rigid body, computes its inertia tensor, sums the total -force and torque on the rigid body each timestep due to forces on its -constituent particles, and integrates the motion of the rigid body. - -If any of the constituent particles of a rigid body are finite-size -particles (spheres or ellipsoids or line segments or triangles), then -their contribution to the inertia tensor of the body is different than -if they were point particles. This means the rotational dynamics of -the rigid body will be different. Thus a model of a dimer is -different if the dimer consists of two point masses versus two -spheroids, even if the two particles have the same mass. Finite-size -particles that experience torque due to their interaction with other -particles will also impart that torque to a rigid body they are part -of. - -See the "fix rigid" command for example of complex rigid-body models -it is possible to define in LAMMPS. - -Note that the "fix shake"_fix_shake.html command can also be used to -treat 2, 3, or 4 particles as a rigid body, but it always assumes the -particles are point masses. - -Also note that body particles cannot be modeled with the "fix -rigid"_fix_rigid.html command. Body particles are treated by LAMMPS -as single particles, though they can store internal state, such as a -list of sub-particles. Individual body partices are typically treated -as rigid bodies, and their motion integrated with a command like "fix -nve/body"_fix_nve_body.html. Interactions between pairs of body -particles are computed via a command like "pair_style -body"_pair_body.html. - -:line - -6.15 Output from LAMMPS (thermo, dumps, computes, fixes, variables) :link(howto_15),h4 - -There are four basic kinds of LAMMPS output: - -"Thermodynamic output"_thermo_style.html, which is a list -of quantities printed every few timesteps to the screen and logfile. :ulb,l - -"Dump files"_dump.html, which contain snapshots of atoms and various -per-atom values and are written at a specified frequency. :l - -Certain fixes can output user-specified quantities to files: "fix -ave/time"_fix_ave_time.html for time averaging, "fix -ave/chunk"_fix_ave_chunk.html for spatial or other averaging, and "fix -print"_fix_print.html for single-line output of -"variables"_variable.html. Fix print can also output to the -screen. :l - -"Restart files"_restart.html. :l -:ule - -A simulation prints one set of thermodynamic output and (optionally) -restart files. It can generate any number of dump files and fix -output files, depending on what "dump"_dump.html and "fix"_fix.html -commands you specify. - -As discussed below, LAMMPS gives you a variety of ways to determine -what quantities are computed and printed when the thermodynamics, -dump, or fix commands listed above perform output. Throughout this -discussion, note that users can also "add their own computes and fixes -to LAMMPS"_Modify.html which can then generate values that can then be -output with these commands. - -The following sub-sections discuss different LAMMPS command related -to output and the kind of data they operate on and produce: - -"Global/per-atom/local data"_#global -"Scalar/vector/array data"_#scalar -"Thermodynamic output"_#thermo -"Dump file output"_#dump -"Fixes that write output files"_#fixoutput -"Computes that process output quantities"_#computeoutput -"Fixes that process output quantities"_#fixprocoutput -"Computes that generate values to output"_#compute -"Fixes that generate values to output"_#fix -"Variables that generate values to output"_#variable -"Summary table of output options and data flow between commands"_#table :ul - -Global/per-atom/local data :h4,link(global) - -Various output-related commands work with three different styles of -data: global, per-atom, or local. A global datum is one or more -system-wide values, e.g. the temperature of the system. A per-atom -datum is one or more values per atom, e.g. the kinetic energy of each -atom. Local datums are calculated by each processor based on the -atoms it owns, but there may be zero or more per atom, e.g. a list of -bond distances. - -Scalar/vector/array data :h4,link(scalar) - -Global, per-atom, and local datums can each come in three kinds: a -single scalar value, a vector of values, or a 2d array of values. The -doc page for a "compute" or "fix" or "variable" that generates data -will specify both the style and kind of data it produces, e.g. a -per-atom vector. - -When a quantity is accessed, as in many of the output commands -discussed below, it can be referenced via the following bracket -notation, where ID in this case is the ID of a compute. The leading -"c_" would be replaced by "f_" for a fix, or "v_" for a variable: - -c_ID | entire scalar, vector, or array -c_ID\[I\] | one element of vector, one column of array -c_ID\[I\]\[J\] | one element of array :tb(s=|) - -In other words, using one bracket reduces the dimension of the data -once (vector -> scalar, array -> vector). Using two brackets reduces -the dimension twice (array -> scalar). Thus a command that uses -scalar values as input can typically also process elements of a vector -or array. - -Thermodynamic output :h4,link(thermo) - -The frequency and format of thermodynamic output is set by the -"thermo"_thermo.html, "thermo_style"_thermo_style.html, and -"thermo_modify"_thermo_modify.html commands. The -"thermo_style"_thermo_style.html command also specifies what values -are calculated and written out. Pre-defined keywords can be specified -(e.g. press, etotal, etc). Three additional kinds of keywords can -also be specified (c_ID, f_ID, v_name), where a "compute"_compute.html -or "fix"_fix.html or "variable"_variable.html provides the value to be -output. In each case, the compute, fix, or variable must generate -global values for input to the "thermo_style custom"_dump.html -command. - -Note that thermodynamic output values can be "extensive" or -"intensive". The former scale with the number of atoms in the system -(e.g. total energy), the latter do not (e.g. temperature). The -setting for "thermo_modify norm"_thermo_modify.html determines whether -extensive quantities are normalized or not. Computes and fixes -produce either extensive or intensive values; see their individual doc -pages for details. "Equal-style variables"_variable.html produce only -intensive values; you can include a division by "natoms" in the -formula if desired, to make an extensive calculation produce an -intensive result. - -Dump file output :h4,link(dump) - -Dump file output is specified by the "dump"_dump.html and -"dump_modify"_dump_modify.html commands. There are several -pre-defined formats (dump atom, dump xtc, etc). - -There is also a "dump custom"_dump.html format where the user -specifies what values are output with each atom. Pre-defined atom -attributes can be specified (id, x, fx, etc). Three additional kinds -of keywords can also be specified (c_ID, f_ID, v_name), where a -"compute"_compute.html or "fix"_fix.html or "variable"_variable.html -provides the values to be output. In each case, the compute, fix, or -variable must generate per-atom values for input to the "dump -custom"_dump.html command. - -There is also a "dump local"_dump.html format where the user specifies -what local values to output. A pre-defined index keyword can be -specified to enumerate the local values. Two additional kinds of -keywords can also be specified (c_ID, f_ID), where a -"compute"_compute.html or "fix"_fix.html or "variable"_variable.html -provides the values to be output. In each case, the compute or fix -must generate local values for input to the "dump local"_dump.html -command. - -Fixes that write output files :h4,link(fixoutput) - -Several fixes take various quantities as input and can write output -files: "fix ave/time"_fix_ave_time.html, "fix -ave/chunk"_fix_ave_chunk.html, "fix ave/histo"_fix_ave_histo.html, -"fix ave/correlate"_fix_ave_correlate.html, and "fix -print"_fix_print.html. - -The "fix ave/time"_fix_ave_time.html command enables direct output to -a file and/or time-averaging of global scalars or vectors. The user -specifies one or more quantities as input. These can be global -"compute"_compute.html values, global "fix"_fix.html values, or -"variables"_variable.html of any style except the atom style which -produces per-atom values. Since a variable can refer to keywords used -by the "thermo_style custom"_thermo_style.html command (like temp or -press) and individual per-atom values, a wide variety of quantities -can be time averaged and/or output in this way. If the inputs are one -or more scalar values, then the fix generate a global scalar or vector -of output. If the inputs are one or more vector values, then the fix -generates a global vector or array of output. The time-averaged -output of this fix can also be used as input to other output commands. - -The "fix ave/chunk"_fix_ave_chunk.html command enables direct output -to a file of chunk-averaged per-atom quantities like those output in -dump files. Chunks can represent spatial bins or other collections of -atoms, e.g. individual molecules. The per-atom quantities can be atom -density (mass or number) or atom attributes such as position, -velocity, force. They can also be per-atom quantities calculated by a -"compute"_compute.html, by a "fix"_fix.html, or by an atom-style -"variable"_variable.html. The chunk-averaged output of this fix can -also be used as input to other output commands. - -The "fix ave/histo"_fix_ave_histo.html command enables direct output -to a file of histogrammed quantities, which can be global or per-atom -or local quantities. The histogram output of this fix can also be -used as input to other output commands. - -The "fix ave/correlate"_fix_ave_correlate.html command enables direct -output to a file of time-correlated quantities, which can be global -values. The correlation matrix output of this fix can also be used as -input to other output commands. - -The "fix print"_fix_print.html command can generate a line of output -written to the screen and log file or to a separate file, periodically -during a running simulation. The line can contain one or more -"variable"_variable.html values for any style variable except the -vector or atom styles). As explained above, variables themselves can -contain references to global values generated by "thermodynamic -keywords"_thermo_style.html, "computes"_compute.html, -"fixes"_fix.html, or other "variables"_variable.html, or to per-atom -values for a specific atom. Thus the "fix print"_fix_print.html -command is a means to output a wide variety of quantities separate -from normal thermodynamic or dump file output. - -Computes that process output quantities :h4,link(computeoutput) - -The "compute reduce"_compute_reduce.html and "compute -reduce/region"_compute_reduce.html commands take one or more per-atom -or local vector quantities as inputs and "reduce" them (sum, min, max, -ave) to scalar quantities. These are produced as output values which -can be used as input to other output commands. - -The "compute slice"_compute_slice.html command take one or more global -vector or array quantities as inputs and extracts a subset of their -values to create a new vector or array. These are produced as output -values which can be used as input to other output commands. - -The "compute property/atom"_compute_property_atom.html command takes a -list of one or more pre-defined atom attributes (id, x, fx, etc) and -stores the values in a per-atom vector or array. These are produced -as output values which can be used as input to other output commands. -The list of atom attributes is the same as for the "dump -custom"_dump.html command. - -The "compute property/local"_compute_property_local.html command takes -a list of one or more pre-defined local attributes (bond info, angle -info, etc) and stores the values in a local vector or array. These -are produced as output values which can be used as input to other -output commands. - -Fixes that process output quantities :h4,link(fixprocoutput) - -The "fix vector"_fix_vector.html command can create global vectors as -output from global scalars as input, accumulating them one element at -a time. - -The "fix ave/atom"_fix_ave_atom.html command performs time-averaging -of per-atom vectors. The per-atom quantities can be atom attributes -such as position, velocity, force. They can also be per-atom -quantities calculated by a "compute"_compute.html, by a -"fix"_fix.html, or by an atom-style "variable"_variable.html. The -time-averaged per-atom output of this fix can be used as input to -other output commands. - -The "fix store/state"_fix_store_state.html command can archive one or -more per-atom attributes at a particular time, so that the old values -can be used in a future calculation or output. The list of atom -attributes is the same as for the "dump custom"_dump.html command, -including per-atom quantities calculated by a "compute"_compute.html, -by a "fix"_fix.html, or by an atom-style "variable"_variable.html. -The output of this fix can be used as input to other output commands. - -Computes that generate values to output :h4,link(compute) - -Every "compute"_compute.html in LAMMPS produces either global or -per-atom or local values. The values can be scalars or vectors or -arrays of data. These values can be output using the other commands -described in this section. The doc page for each compute command -describes what it produces. Computes that produce per-atom or local -values have the word "atom" or "local" in their style name. Computes -without the word "atom" or "local" produce global values. - -Fixes that generate values to output :h4,link(fix) - -Some "fixes"_fix.html in LAMMPS produces either global or per-atom or -local values which can be accessed by other commands. The values can -be scalars or vectors or arrays of data. These values can be output -using the other commands described in this section. The doc page for -each fix command tells whether it produces any output quantities and -describes them. - -Variables that generate values to output :h4,link(variable) - -"Variables"_variable.html defined in an input script can store one or -more strings. But equal-style, vector-style, and atom-style or -atomfile-style variables generate a global scalar value, global vector -or values, or a per-atom vector, respectively, when accessed. The -formulas used to define these variables can contain references to the -thermodynamic keywords and to global and per-atom data generated by -computes, fixes, and other variables. The values generated by -variables can be used as input to and thus output by the other -commands described in this section. - -Summary table of output options and data flow between commands :h4,link(table) - -This table summarizes the various commands that can be used for -generating output from LAMMPS. Each command produces output data of -some kind and/or writes data to a file. Most of the commands can take -data from other commands as input. Thus you can link many of these -commands together in pipeline form, where data produced by one command -is used as input to another command and eventually written to the -screen or to a file. Note that to hook two commands together the -output and input data types must match, e.g. global/per-atom/local -data and scalar/vector/array data. - -Also note that, as described above, when a command takes a scalar as -input, that could be an element of a vector or array. Likewise a -vector input could be a column of an array. - -Command: Input: Output: -"thermo_style custom"_thermo_style.html: global scalars: screen, log file: -"dump custom"_dump.html: per-atom vectors: dump file: -"dump local"_dump.html: local vectors: dump file: -"fix print"_fix_print.html: global scalar from variable: screen, file: -"print"_print.html: global scalar from variable: screen: -"computes"_compute.html: N/A: global/per-atom/local scalar/vector/array: -"fixes"_fix.html: N/A: global/per-atom/local scalar/vector/array: -"variables"_variable.html: global scalars and vectors, per-atom vectors: global scalar and vector, per-atom vector: -"compute reduce"_compute_reduce.html: per-atom/local vectors: global scalar/vector: -"compute slice"_compute_slice.html: global vectors/arrays: global vector/array: -"compute property/atom"_compute_property_atom.html: per-atom vectors: per-atom vector/array: -"compute property/local"_compute_property_local.html: local vectors: local vector/array: -"fix vector"_fix_vector.html: global scalars: global vector: -"fix ave/atom"_fix_ave_atom.html: per-atom vectors: per-atom vector/array: -"fix ave/time"_fix_ave_time.html: global scalars/vectors: global scalar/vector/array, file: -"fix ave/chunk"_fix_ave_chunk.html: per-atom vectors: global array, file: -"fix ave/histo"_fix_ave_histo.html: global/per-atom/local scalars and vectors: global array, file: -"fix ave/correlate"_fix_ave_correlate.html: global scalars: global array, file: -"fix store/state"_fix_store_state.html: per-atom vectors: per-atom vector/array :tb(c=3,s=:) - -:line - -6.16 Thermostatting, barostatting, and computing temperature :link(howto_16),h4 - -Thermostatting means controlling the temperature of particles in an MD -simulation. Barostatting means controlling the pressure. Since the -pressure includes a kinetic component due to particle velocities, both -these operations require calculation of the temperature. Typically a -target temperature (T) and/or pressure (P) is specified by the user, -and the thermostat or barostat attempts to equilibrate the system to -the requested T and/or P. - -Temperature is computed as kinetic energy divided by some number of -degrees of freedom (and the Boltzmann constant). Since kinetic energy -is a function of particle velocity, there is often a need to -distinguish between a particle's advection velocity (due to some -aggregate motion of particles) and its thermal velocity. The sum of -the two is the particle's total velocity, but the latter is often what -is wanted to compute a temperature. - -LAMMPS has several options for computing temperatures, any of which -can be used in thermostatting and barostatting. These "compute -commands"_compute.html calculate temperature, and the "compute -pressure"_compute_pressure.html command calculates pressure. - -"compute temp"_compute_temp.html -"compute temp/sphere"_compute_temp_sphere.html -"compute temp/asphere"_compute_temp_asphere.html -"compute temp/com"_compute_temp_com.html -"compute temp/deform"_compute_temp_deform.html -"compute temp/partial"_compute_temp_partial.html -"compute temp/profile"_compute_temp_profile.html -"compute temp/ramp"_compute_temp_ramp.html -"compute temp/region"_compute_temp_region.html :ul - -All but the first 3 calculate velocity biases directly (e.g. advection -velocities) that are removed when computing the thermal temperature. -"Compute temp/sphere"_compute_temp_sphere.html and "compute -temp/asphere"_compute_temp_asphere.html compute kinetic energy for -finite-size particles that includes rotational degrees of freedom. -They both allow for velocity biases indirectly, via an optional extra -argument, another temperature compute that subtracts a velocity bias. -This allows the translational velocity of spherical or aspherical -particles to be adjusted in prescribed ways. - -Thermostatting in LAMMPS is performed by "fixes"_fix.html, or in one -case by a pair style. Several thermostatting fixes are available: -Nose-Hoover (nvt), Berendsen, CSVR, Langevin, and direct rescaling -(temp/rescale). Dissipative particle dynamics (DPD) thermostatting -can be invoked via the {dpd/tstat} pair style: - -"fix nvt"_fix_nh.html -"fix nvt/sphere"_fix_nvt_sphere.html -"fix nvt/asphere"_fix_nvt_asphere.html -"fix nvt/sllod"_fix_nvt_sllod.html -"fix temp/berendsen"_fix_temp_berendsen.html -"fix temp/csvr"_fix_temp_csvr.html -"fix langevin"_fix_langevin.html -"fix temp/rescale"_fix_temp_rescale.html -"pair_style dpd/tstat"_pair_dpd.html :ul - -"Fix nvt"_fix_nh.html only thermostats the translational velocity of -particles. "Fix nvt/sllod"_fix_nvt_sllod.html also does this, except -that it subtracts out a velocity bias due to a deforming box and -integrates the SLLOD equations of motion. See the "NEMD -simulations"_#howto_13 section of this page for further details. "Fix -nvt/sphere"_fix_nvt_sphere.html and "fix -nvt/asphere"_fix_nvt_asphere.html thermostat not only translation -velocities but also rotational velocities for spherical and aspherical -particles. - -DPD thermostatting alters pairwise interactions in a manner analogous -to the per-particle thermostatting of "fix -langevin"_fix_langevin.html. - -Any of the thermostatting fixes can use temperature computes that -remove bias which has two effects. First, the current calculated -temperature, which is compared to the requested target temperature, is -calculated with the velocity bias removed. Second, the thermostat -adjusts only the thermal temperature component of the particle's -velocities, which are the velocities with the bias removed. The -removed bias is then added back to the adjusted velocities. See the -doc pages for the individual fixes and for the -"fix_modify"_fix_modify.html command for instructions on how to assign -a temperature compute to a thermostatting fix. For example, you can -apply a thermostat to only the x and z components of velocity by using -it in conjunction with "compute -temp/partial"_compute_temp_partial.html. Of you could thermostat only -the thermal temperature of a streaming flow of particles without -affecting the streaming velocity, by using "compute -temp/profile"_compute_temp_profile.html. - -NOTE: Only the nvt fixes perform time integration, meaning they update -the velocities and positions of particles due to forces and velocities -respectively. The other thermostat fixes only adjust velocities; they -do NOT perform time integration updates. Thus they should be used in -conjunction with a constant NVE integration fix such as these: - -"fix nve"_fix_nve.html -"fix nve/sphere"_fix_nve_sphere.html -"fix nve/asphere"_fix_nve_asphere.html :ul - -Barostatting in LAMMPS is also performed by "fixes"_fix.html. Two -barosttating methods are currently available: Nose-Hoover (npt and -nph) and Berendsen: - -"fix npt"_fix_nh.html -"fix npt/sphere"_fix_npt_sphere.html -"fix npt/asphere"_fix_npt_asphere.html -"fix nph"_fix_nh.html -"fix press/berendsen"_fix_press_berendsen.html :ul - -The "fix npt"_fix_nh.html commands include a Nose-Hoover thermostat -and barostat. "Fix nph"_fix_nh.html is just a Nose/Hoover barostat; -it does no thermostatting. Both "fix nph"_fix_nh.html and "fix -press/berendsen"_fix_press_berendsen.html can be used in conjunction -with any of the thermostatting fixes. - -As with the thermostats, "fix npt"_fix_nh.html and "fix -nph"_fix_nh.html only use translational motion of the particles in -computing T and P and performing thermo/barostatting. "Fix -npt/sphere"_fix_npt_sphere.html and "fix -npt/asphere"_fix_npt_asphere.html thermo/barostat using not only -translation velocities but also rotational velocities for spherical -and aspherical particles. - -All of the barostatting fixes use the "compute -pressure"_compute_pressure.html compute to calculate a current -pressure. By default, this compute is created with a simple "compute -temp"_compute_temp.html (see the last argument of the "compute -pressure"_compute_pressure.html command), which is used to calculated -the kinetic component of the pressure. The barostatting fixes can -also use temperature computes that remove bias for the purpose of -computing the kinetic component which contributes to the current -pressure. See the doc pages for the individual fixes and for the -"fix_modify"_fix_modify.html command for instructions on how to assign -a temperature or pressure compute to a barostatting fix. - -NOTE: As with the thermostats, the Nose/Hoover methods ("fix -npt"_fix_nh.html and "fix nph"_fix_nh.html) perform time integration. -"Fix press/berendsen"_fix_press_berendsen.html does NOT, so it should -be used with one of the constant NVE fixes or with one of the NVT -fixes. - -Finally, thermodynamic output, which can be setup via the -"thermo_style"_thermo_style.html command, often includes temperature -and pressure values. As explained on the doc page for the -"thermo_style"_thermo_style.html command, the default T and P are -setup by the thermo command itself. They are NOT the ones associated -with any thermostatting or barostatting fix you have defined or with -any compute that calculates a temperature or pressure. Thus if you -want to view these values of T and P, you need to specify them -explicitly via a "thermo_style custom"_thermo_style.html command. Or -you can use the "thermo_modify"_thermo_modify.html command to -re-define what temperature or pressure compute is used for default -thermodynamic output. - -:line - -6.17 Walls :link(howto_17),h4 - -Walls in an MD simulation are typically used to bound particle motion, -i.e. to serve as a boundary condition. - -Walls in LAMMPS can be of rough (made of particles) or idealized -surfaces. Ideal walls can be smooth, generating forces only in the -normal direction, or frictional, generating forces also in the -tangential direction. - -Rough walls, built of particles, can be created in various ways. The -particles themselves can be generated like any other particle, via the -"lattice"_lattice.html and "create_atoms"_create_atoms.html commands, -or read in via the "read_data"_read_data.html command. - -Their motion can be constrained by many different commands, so that -they do not move at all, move together as a group at constant velocity -or in response to a net force acting on them, move in a prescribed -fashion (e.g. rotate around a point), etc. Note that if a time -integration fix like "fix nve"_fix_nve.html or "fix nvt"_fix_nh.html -is not used with the group that contains wall particles, their -positions and velocities will not be updated. - -"fix aveforce"_fix_aveforce.html - set force on particles to average value, so they move together -"fix setforce"_fix_setforce.html - set force on particles to a value, e.g. 0.0 -"fix freeze"_fix_freeze.html - freeze particles for use as granular walls -"fix nve/noforce"_fix_nve_noforce.html - advect particles by their velocity, but without force -"fix move"_fix_move.html - prescribe motion of particles by a linear velocity, oscillation, rotation, variable :ul - -The "fix move"_fix_move.html command offers the most generality, since -the motion of individual particles can be specified with -"variable"_variable.html formula which depends on time and/or the -particle position. - -For rough walls, it may be useful to turn off pairwise interactions -between wall particles via the "neigh_modify -exclude"_neigh_modify.html command. - -Rough walls can also be created by specifying frozen particles that do -not move and do not interact with mobile particles, and then tethering -other particles to the fixed particles, via a "bond"_bond_style.html. -The bonded particles do interact with other mobile particles. - -Idealized walls can be specified via several fix commands. "Fix -wall/gran"_fix_wall_gran.html creates frictional walls for use with -granular particles; all the other commands create smooth walls. - -"fix wall/reflect"_fix_wall_reflect.html - reflective flat walls -"fix wall/lj93"_fix_wall.html - flat walls, with Lennard-Jones 9/3 potential -"fix wall/lj126"_fix_wall.html - flat walls, with Lennard-Jones 12/6 potential -"fix wall/colloid"_fix_wall.html - flat walls, with "pair_style colloid"_pair_colloid.html potential -"fix wall/harmonic"_fix_wall.html - flat walls, with repulsive harmonic spring potential -"fix wall/region"_fix_wall_region.html - use region surface as wall -"fix wall/gran"_fix_wall_gran.html - flat or curved walls with "pair_style granular"_pair_gran.html potential :ul - -The {lj93}, {lj126}, {colloid}, and {harmonic} styles all allow the -flat walls to move with a constant velocity, or oscillate in time. -The "fix wall/region"_fix_wall_region.html command offers the most -generality, since the region surface is treated as a wall, and the -geometry of the region can be a simple primitive volume (e.g. a -sphere, or cube, or plane), or a complex volume made from the union -and intersection of primitive volumes. "Regions"_region.html can also -specify a volume "interior" or "exterior" to the specified primitive -shape or {union} or {intersection}. "Regions"_region.html can also be -"dynamic" meaning they move with constant velocity, oscillate, or -rotate. - -The only frictional idealized walls currently in LAMMPS are flat or -curved surfaces specified by the "fix wall/gran"_fix_wall_gran.html -command. At some point we plan to allow regoin surfaces to be used as -frictional walls, as well as triangulated surfaces. - -:line - -6.18 Elastic constants :link(howto_18),h4 - -Elastic constants characterize the stiffness of a material. The formal -definition is provided by the linear relation that holds between the -stress and strain tensors in the limit of infinitesimal deformation. -In tensor notation, this is expressed as s_ij = C_ijkl * e_kl, where -the repeated indices imply summation. s_ij are the elements of the -symmetric stress tensor. e_kl are the elements of the symmetric strain -tensor. C_ijkl are the elements of the fourth rank tensor of elastic -constants. In three dimensions, this tensor has 3^4=81 elements. Using -Voigt notation, the tensor can be written as a 6x6 matrix, where C_ij -is now the derivative of s_i w.r.t. e_j. Because s_i is itself a -derivative w.r.t. e_i, it follows that C_ij is also symmetric, with at -most 7*6/2 = 21 distinct elements. - -At zero temperature, it is easy to estimate these derivatives by -deforming the simulation box in one of the six directions using the -"change_box"_change_box.html command and measuring the change in the -stress tensor. A general-purpose script that does this is given in the -examples/elastic directory described on the "Examples"_Examples.html -doc page. - -Calculating elastic constants at finite temperature is more -challenging, because it is necessary to run a simulation that perfoms -time averages of differential properties. One way to do this is to -measure the change in average stress tensor in an NVT simulations when -the cell volume undergoes a finite deformation. In order to balance -the systematic and statistical errors in this method, the magnitude of -the deformation must be chosen judiciously, and care must be taken to -fully equilibrate the deformed cell before sampling the stress -tensor. Another approach is to sample the triclinic cell fluctuations -that occur in an NPT simulation. This method can also be slow to -converge and requires careful post-processing "(Shinoda)"_#Shinoda1 - -:line - -6.19 Library interface to LAMMPS :link(howto_19),h4 - -As described in "Section 2.5"_Section_start.html#start_5, LAMMPS can -be built as a library, so that it can be called by another code, used -in a "coupled manner"_Section_howto.html#howto_10 with other codes, or -driven through a "Python interface"_Python.html. - -All of these methodologies use a C-style interface to LAMMPS that is -provided in the files src/library.cpp and src/library.h. The -functions therein have a C-style argument list, but contain C++ code -you could write yourself in a C++ application that was invoking LAMMPS -directly. The C++ code in the functions illustrates how to invoke -internal LAMMPS operations. Note that LAMMPS classes are defined -within a LAMMPS namespace (LAMMPS_NS) if you use them from another C++ -application. - -The examples/COUPLE and python/examples directories have example C++ -and C and Python codes which show how a driver code can link to LAMMPS -as a library, run LAMMPS on a subset of processors, grab data from -LAMMPS, change it, and put it back into LAMMPS. - -The file src/library.cpp contains the following functions for creating -and destroying an instance of LAMMPS and sending it commands to -execute. See the documentation in the src/library.cpp file for -details. - -NOTE: You can write code for additional functions as needed to define -how your code talks to LAMMPS and add them to src/library.cpp and -src/library.h, as well as to the "Python interface"_Python.html. The -added functions can access or change any internal LAMMPS data you -wish. - -void lammps_open(int, char **, MPI_Comm, void **) -void lammps_open_no_mpi(int, char **, void **) -void lammps_close(void *) -int lammps_version(void *) -void lammps_file(void *, char *) -char *lammps_command(void *, char *) -void lammps_commands_list(void *, int, char **) -void lammps_commands_string(void *, char *) -void lammps_free(void *) :pre - -The lammps_open() function is used to initialize LAMMPS, passing in a -list of strings as if they were "command-line -arguments"_Section_start.html#start_6 when LAMMPS is run in -stand-alone mode from the command line, and a MPI communicator for -LAMMPS to run under. It returns a ptr to the LAMMPS object that is -created, and which is used in subsequent library calls. The -lammps_open() function can be called multiple times, to create -multiple instances of LAMMPS. - -LAMMPS will run on the set of processors in the communicator. This -means the calling code can run LAMMPS on all or a subset of -processors. For example, a wrapper script might decide to alternate -between LAMMPS and another code, allowing them both to run on all the -processors. Or it might allocate half the processors to LAMMPS and -half to the other code and run both codes simultaneously before -syncing them up periodically. Or it might instantiate multiple -instances of LAMMPS to perform different calculations. - -The lammps_open_no_mpi() function is similar except that no MPI -communicator is passed from the caller. Instead, MPI_COMM_WORLD is -used to instantiate LAMMPS, and MPI is initialized if necessary. - -The lammps_close() function is used to shut down an instance of LAMMPS -and free all its memory. - -The lammps_version() function can be used to determined the specific -version of the underlying LAMMPS code. This is particularly useful -when loading LAMMPS as a shared library via dlopen(). The code using -the library interface can than use this information to adapt to -changes to the LAMMPS command syntax between versions. The returned -LAMMPS version code is an integer (e.g. 2 Sep 2015 results in -20150902) that grows with every new LAMMPS version. - -The lammps_file(), lammps_command(), lammps_commands_list(), and -lammps_commands_string() functions are used to pass one or more -commands to LAMMPS to execute, the same as if they were coming from an -input script. - -Via these functions, the calling code can read or generate a series of -LAMMPS commands one or multiple at a time and pass it thru the library -interface to setup a problem and then run it in stages. The caller -can interleave the command function calls with operations it performs, -calls to extract information from or set information within LAMMPS, or -calls to another code's library. - -The lammps_file() function passes the filename of an input script. -The lammps_command() function passes a single command as a string. -The lammps_commands_list() function passes multiple commands in a -char** list. In both lammps_command() and lammps_commands_list(), -individual commands may or may not have a trailing newline. The -lammps_commands_string() function passes multiple commands -concatenated into one long string, separated by newline characters. -In both lammps_commands_list() and lammps_commands_string(), a single -command can be spread across multiple lines, if the last printable -character of all but the last line is "&", the same as if the lines -appeared in an input script. - -The lammps_free() function is a clean-up function to free memory that -the library allocated previously via other function calls. See -comments in src/library.cpp file for which other functions need this -clean-up. - -The file src/library.cpp also contains these functions for extracting -information from LAMMPS and setting value within LAMMPS. Again, see -the documentation in the src/library.cpp file for details, including -which quantities can be queried by name: - -int lammps_extract_setting(void *, char *) -void *lammps_extract_global(void *, char *) -void lammps_extract_box(void *, double *, double *, - double *, double *, double *, int *, int *) -void *lammps_extract_atom(void *, char *) -void *lammps_extract_compute(void *, char *, int, int) -void *lammps_extract_fix(void *, char *, int, int, int, int) -void *lammps_extract_variable(void *, char *, char *) :pre - -The extract_setting() function returns info on the size -of data types (e.g. 32-bit or 64-bit atom IDs) used -by the LAMMPS executable (a compile-time choice). - -The other extract functions return a pointer to various global or -per-atom quantities stored in LAMMPS or to values calculated by a -compute, fix, or variable. The pointer returned by the -extract_global() function can be used as a permanent reference to a -value which may change. For the extract_atom() method, see the -extract() method in the src/atom.cpp file for a list of valid per-atom -properties. New names could easily be added if the property you want -is not listed. For the other extract functions, the underlying -storage may be reallocated as LAMMPS runs, so you need to re-call the -function to assure a current pointer or returned value(s). - -double lammps_get_thermo(void *, char *) -int lammps_get_natoms(void *) :pre - -int lammps_set_variable(void *, char *, char *) -void lammps_reset_box(void *, double *, double *, double, double, double) :pre - -The lammps_get_thermo() function returns the current value of a thermo -keyword as a double precision value. - -The lammps_get_natoms() function returns the total number of atoms in -the system and can be used by the caller to allocate memory for the -lammps_gather_atoms() and lammps_scatter_atoms() functions. - -The lammps_set_variable() function can set an existing string-style -variable to a new string value, so that subsequent LAMMPS commands can -access the variable. - -The lammps_reset_box() function resets the size and shape of the -simulation box, e.g. as part of restoring a previously extracted and -saved state of a simulation. - -void lammps_gather_atoms(void *, char *, int, int, void *) -void lammps_gather_atoms_concat(void *, char *, int, int, void *) -void lammps_gather_atoms_subset(void *, char *, int, int, int, int *, void *) -void lammps_scatter_atoms(void *, char *, int, int, void *) -void lammps_scatter_atoms_subset(void *, char *, int, int, int, int *, void *) :pre - -void lammps_create_atoms(void *, int, tagint *, int *, double *, double *, - imageint *, int) :pre - -The gather functions collect peratom info of the requested type (atom -coords, atom types, forces, etc) from all processors, and returns the -same vector of values to each callling processor. The scatter -functions do the inverse. They distribute a vector of peratom values, -passed by all calling processors, to invididual atoms, which may be -owned by different processos. - -The lammps_gather_atoms() function does this for all N atoms in the -system, ordered by atom ID, from 1 to N. The -lammps_gather_atoms_concat() function does it for all N atoms, but -simply concatenates the subset of atoms owned by each processor. The -resulting vector is not ordered by atom ID. Atom IDs can be requetsed -by the same function if the caller needs to know the ordering. The -lammps_gather_subset() function allows the caller to request values -for only a subset of atoms (identified by ID). -For all 3 gather function, per-atom image flags can be retrieved in 2 ways. -If the count is specified as 1, they are returned -in a packed format with all three image flags stored in a single integer. -If the count is specified as 3, the values are unpacked into xyz flags -by the library before returning them. - -The lammps_scatter_atoms() function takes a list of values for all N -atoms in the system, ordered by atom ID, from 1 to N, and assigns -those values to each atom in the system. The -lammps_scatter_atoms_subset() function takes a subset of IDs as an -argument and only scatters those values to the owning atoms. - -The lammps_create_atoms() function takes a list of N atoms as input -with atom types and coords (required), an optionally atom IDs and -velocities and image flags. It uses the coords of each atom to assign -it as a new atom to the processor that owns it. This function is -useful to add atoms to a simulation or (in tandem with -lammps_reset_box()) to restore a previously extracted and saved state -of a simulation. Additional properties for the new atoms can then be -assigned via the lammps_scatter_atoms() or lammps_extract_atom() -functions. - -:line - -6.20 Calculating thermal conductivity :link(howto_20),h4 - -The thermal conductivity kappa of a material can be measured in at -least 4 ways using various options in LAMMPS. See the examples/KAPPA -directory for scripts that implement the 4 methods discussed here for -a simple Lennard-Jones fluid model. Also, see "this -section"_Section_howto.html#howto_21 of the manual for an analogous -discussion for viscosity. - -The thermal conductivity tensor kappa is a measure of the propensity -of a material to transmit heat energy in a diffusive manner as given -by Fourier's law - -J = -kappa grad(T) - -where J is the heat flux in units of energy per area per time and -grad(T) is the spatial gradient of temperature. The thermal -conductivity thus has units of energy per distance per time per degree -K and is often approximated as an isotropic quantity, i.e. as a -scalar. - -The first method is to setup two thermostatted regions at opposite -ends of a simulation box, or one in the middle and one at the end of a -periodic box. By holding the two regions at different temperatures -with a "thermostatting fix"_Section_howto.html#howto_13, the energy -added to the hot region should equal the energy subtracted from the -cold region and be proportional to the heat flux moving between the -regions. See the papers by "Ikeshoji and Hafskjold"_#howto-Ikeshoji -and "Wirnsberger et al"_#howto-Wirnsberger for details of this idea. -Note that thermostatting fixes such as "fix nvt"_fix_nh.html, "fix -langevin"_fix_langevin.html, and "fix -temp/rescale"_fix_temp_rescale.html store the cumulative energy they -add/subtract. - -Alternatively, as a second method, the "fix heat"_fix_heat.html or -"fix ehex"_fix_ehex.html commands can be used in place of thermostats -on each of two regions to add/subtract specified amounts of energy to -both regions. In both cases, the resulting temperatures of the two -regions can be monitored with the "compute temp/region" command and -the temperature profile of the intermediate region can be monitored -with the "fix ave/chunk"_fix_ave_chunk.html and "compute -ke/atom"_compute_ke_atom.html commands. - -The third method is to perform a reverse non-equilibrium MD simulation -using the "fix thermal/conductivity"_fix_thermal_conductivity.html -command which implements the rNEMD algorithm of Muller-Plathe. -Kinetic energy is swapped between atoms in two different layers of the -simulation box. This induces a temperature gradient between the two -layers which can be monitored with the "fix -ave/chunk"_fix_ave_chunk.html and "compute -ke/atom"_compute_ke_atom.html commands. The fix tallies the -cumulative energy transfer that it performs. See the "fix -thermal/conductivity"_fix_thermal_conductivity.html command for -details. - -The fourth method is based on the Green-Kubo (GK) formula which -relates the ensemble average of the auto-correlation of the heat flux -to kappa. The heat flux can be calculated from the fluctuations of -per-atom potential and kinetic energies and per-atom stress tensor in -a steady-state equilibrated simulation. This is in contrast to the -two preceding non-equilibrium methods, where energy flows continuously -between hot and cold regions of the simulation box. - -The "compute heat/flux"_compute_heat_flux.html command can calculate -the needed heat flux and describes how to implement the Green_Kubo -formalism using additional LAMMPS commands, such as the "fix -ave/correlate"_fix_ave_correlate.html command to calculate the needed -auto-correlation. See the doc page for the "compute -heat/flux"_compute_heat_flux.html command for an example input script -that calculates the thermal conductivity of solid Ar via the GK -formalism. - -:line - -6.21 Calculating viscosity :link(howto_21),h4 - -The shear viscosity eta of a fluid can be measured in at least 5 ways -using various options in LAMMPS. See the examples/VISCOSITY directory -for scripts that implement the 5 methods discussed here for a simple -Lennard-Jones fluid model. Also, see "this -section"_Section_howto.html#howto_20 of the manual for an analogous -discussion for thermal conductivity. - -Eta is a measure of the propensity of a fluid to transmit momentum in -a direction perpendicular to the direction of velocity or momentum -flow. Alternatively it is the resistance the fluid has to being -sheared. It is given by - -J = -eta grad(Vstream) - -where J is the momentum flux in units of momentum per area per time. -and grad(Vstream) is the spatial gradient of the velocity of the fluid -moving in another direction, normal to the area through which the -momentum flows. Viscosity thus has units of pressure-time. - -The first method is to perform a non-equilibrium MD (NEMD) simulation -by shearing the simulation box via the "fix deform"_fix_deform.html -command, and using the "fix nvt/sllod"_fix_nvt_sllod.html command to -thermostat the fluid via the SLLOD equations of motion. -Alternatively, as a second method, one or more moving walls can be -used to shear the fluid in between them, again with some kind of -thermostat that modifies only the thermal (non-shearing) components of -velocity to prevent the fluid from heating up. - -In both cases, the velocity profile setup in the fluid by this -procedure can be monitored by the "fix -ave/chunk"_fix_ave_chunk.html command, which determines -grad(Vstream) in the equation above. E.g. the derivative in the -y-direction of the Vx component of fluid motion or grad(Vstream) = -dVx/dy. The Pxy off-diagonal component of the pressure or stress -tensor, as calculated by the "compute pressure"_compute_pressure.html -command, can also be monitored, which is the J term in the equation -above. See "this section"_Section_howto.html#howto_13 of the manual -for details on NEMD simulations. - -The third method is to perform a reverse non-equilibrium MD simulation -using the "fix viscosity"_fix_viscosity.html command which implements -the rNEMD algorithm of Muller-Plathe. Momentum in one dimension is -swapped between atoms in two different layers of the simulation box in -a different dimension. This induces a velocity gradient which can be -monitored with the "fix ave/chunk"_fix_ave_chunk.html command. -The fix tallies the cumulative momentum transfer that it performs. -See the "fix viscosity"_fix_viscosity.html command for details. - -The fourth method is based on the Green-Kubo (GK) formula which -relates the ensemble average of the auto-correlation of the -stress/pressure tensor to eta. This can be done in a fully -equilibrated simulation which is in contrast to the two preceding -non-equilibrium methods, where momentum flows continuously through the -simulation box. - -Here is an example input script that calculates the viscosity of -liquid Ar via the GK formalism: - -# Sample LAMMPS input script for viscosity of liquid Ar :pre - -units real -variable T equal 86.4956 -variable V equal vol -variable dt equal 4.0 -variable p equal 400 # correlation length -variable s equal 5 # sample interval -variable d equal $p*$s # dump interval :pre - -# convert from LAMMPS real units to SI :pre - -variable kB equal 1.3806504e-23 # \[J/K/] Boltzmann -variable atm2Pa equal 101325.0 -variable A2m equal 1.0e-10 -variable fs2s equal 1.0e-15 -variable convert equal $\{atm2Pa\}*$\{atm2Pa\}*$\{fs2s\}*$\{A2m\}*$\{A2m\}*$\{A2m\} :pre - -# setup problem :pre - -dimension 3 -boundary p p p -lattice fcc 5.376 orient x 1 0 0 orient y 0 1 0 orient z 0 0 1 -region box block 0 4 0 4 0 4 -create_box 1 box -create_atoms 1 box -mass 1 39.948 -pair_style lj/cut 13.0 -pair_coeff * * 0.2381 3.405 -timestep $\{dt\} -thermo $d :pre - -# equilibration and thermalization :pre - -velocity all create $T 102486 mom yes rot yes dist gaussian -fix NVT all nvt temp $T $T 10 drag 0.2 -run 8000 :pre - -# viscosity calculation, switch to NVE if desired :pre - -#unfix NVT -#fix NVE all nve :pre - -reset_timestep 0 -variable pxy equal pxy -variable pxz equal pxz -variable pyz equal pyz -fix SS all ave/correlate $s $p $d & - v_pxy v_pxz v_pyz type auto file S0St.dat ave running -variable scale equal $\{convert\}/($\{kB\}*$T)*$V*$s*$\{dt\} -variable v11 equal trap(f_SS\[3\])*$\{scale\} -variable v22 equal trap(f_SS\[4\])*$\{scale\} -variable v33 equal trap(f_SS\[5\])*$\{scale\} -thermo_style custom step temp press v_pxy v_pxz v_pyz v_v11 v_v22 v_v33 -run 100000 -variable v equal (v_v11+v_v22+v_v33)/3.0 -variable ndens equal count(all)/vol -print "average viscosity: $v \[Pa.s\] @ $T K, $\{ndens\} /A^3" :pre - -The fifth method is related to the above Green-Kubo method, -but uses the Einstein formulation, analogous to the Einstein -mean-square-displacement formulation for self-diffusivity. The -time-integrated momentum fluxes play the role of Cartesian -coordinates, whose mean-square displacement increases linearly -with time at sufficiently long times. - -:line - -6.22 Calculating a diffusion coefficient :link(howto_22),h4 - -The diffusion coefficient D of a material can be measured in at least -2 ways using various options in LAMMPS. See the examples/DIFFUSE -directory for scripts that implement the 2 methods discussed here for -a simple Lennard-Jones fluid model. - -The first method is to measure the mean-squared displacement (MSD) of -the system, via the "compute msd"_compute_msd.html command. The slope -of the MSD versus time is proportional to the diffusion coefficient. -The instantaneous MSD values can be accumulated in a vector via the -"fix vector"_fix_vector.html command, and a line fit to the vector to -compute its slope via the "variable slope"_variable.html function, and -thus extract D. - -The second method is to measure the velocity auto-correlation function -(VACF) of the system, via the "compute vacf"_compute_vacf.html -command. The time-integral of the VACF is proportional to the -diffusion coefficient. The instantaneous VACF values can be -accumulated in a vector via the "fix vector"_fix_vector.html command, -and time integrated via the "variable trap"_variable.html function, -and thus extract D. - -:line - -6.23 Using chunks to calculate system properties :link(howto_23),h4 - -In LAMMS, "chunks" are collections of atoms, as defined by the -"compute chunk/atom"_compute_chunk_atom.html command, which assigns -each atom to a chunk ID (or to no chunk at all). The number of chunks -and the assignment of chunk IDs to atoms can be static or change over -time. Examples of "chunks" are molecules or spatial bins or atoms -with similar values (e.g. coordination number or potential energy). - -The per-atom chunk IDs can be used as input to two other kinds of -commands, to calculate various properties of a system: - -"fix ave/chunk"_fix_ave_chunk.html -any of the "compute */chunk"_compute.html commands :ul - -Here, each of the 3 kinds of chunk-related commands is briefly -overviewed. Then some examples are given of how to compute different -properties with chunk commands. - -Compute chunk/atom command: :h4 - -This compute can assign atoms to chunks of various styles. Only atoms -in the specified group and optional specified region are assigned to a -chunk. Here are some possible chunk definitions: - -atoms in same molecule | chunk ID = molecule ID | -atoms of same atom type | chunk ID = atom type | -all atoms with same atom property (charge, radius, etc) | chunk ID = output of compute property/atom | -atoms in same cluster | chunk ID = output of "compute cluster/atom"_compute_cluster_atom.html command | -atoms in same spatial bin | chunk ID = bin ID | -atoms in same rigid body | chunk ID = molecule ID used to define rigid bodies | -atoms with similar potential energy | chunk ID = output of "compute pe/atom"_compute_pe_atom.html | -atoms with same local defect structure | chunk ID = output of "compute centro/atom"_compute_centro_atom.html or "compute coord/atom"_compute_coord_atom.html command :tb(s=|,c=2) - -Note that chunk IDs are integer values, so for atom properties or -computes that produce a floating point value, they will be truncated -to an integer. You could also use the compute in a variable that -scales the floating point value to spread it across multiple integers. - -Spatial bins can be of various kinds, e.g. 1d bins = slabs, 2d bins = -pencils, 3d bins = boxes, spherical bins, cylindrical bins. - -This compute also calculates the number of chunks {Nchunk}, which is -used by other commands to tally per-chunk data. {Nchunk} can be a -static value or change over time (e.g. the number of clusters). The -chunk ID for an individual atom can also be static (e.g. a molecule -ID), or dynamic (e.g. what spatial bin an atom is in as it moves). - -Note that this compute allows the per-atom output of other -"computes"_compute.html, "fixes"_fix.html, and -"variables"_variable.html to be used to define chunk IDs for each -atom. This means you can write your own compute or fix to output a -per-atom quantity to use as chunk ID. See the "Modify"_Modify.html -doc page for how to do this. You can also define a "per-atom -variable"_variable.html in the input script that uses a formula to -generate a chunk ID for each atom. - -Fix ave/chunk command: :h4 - -This fix takes the ID of a "compute -chunk/atom"_compute_chunk_atom.html command as input. For each chunk, -it then sums one or more specified per-atom values over the atoms in -each chunk. The per-atom values can be any atom property, such as -velocity, force, charge, potential energy, kinetic energy, stress, -etc. Additional keywords are defined for per-chunk properties like -density and temperature. More generally any per-atom value generated -by other "computes"_compute.html, "fixes"_fix.html, and "per-atom -variables"_variable.html, can be summed over atoms in each chunk. - -Similar to other averaging fixes, this fix allows the summed per-chunk -values to be time-averaged in various ways, and output to a file. The -fix produces a global array as output with one row of values per -chunk. - -Compute */chunk commands: :h4 - -Currently the following computes operate on chunks of atoms to produce -per-chunk values. - -"compute com/chunk"_compute_com_chunk.html -"compute gyration/chunk"_compute_gyration_chunk.html -"compute inertia/chunk"_compute_inertia_chunk.html -"compute msd/chunk"_compute_msd_chunk.html -"compute property/chunk"_compute_property_chunk.html -"compute temp/chunk"_compute_temp_chunk.html -"compute torque/chunk"_compute_vcm_chunk.html -"compute vcm/chunk"_compute_vcm_chunk.html :ul - -They each take the ID of a "compute -chunk/atom"_compute_chunk_atom.html command as input. As their names -indicate, they calculate the center-of-mass, radius of gyration, -moments of inertia, mean-squared displacement, temperature, torque, -and velocity of center-of-mass for each chunk of atoms. The "compute -property/chunk"_compute_property_chunk.html command can tally the -count of atoms in each chunk and extract other per-chunk properties. - -The reason these various calculations are not part of the "fix -ave/chunk command"_fix_ave_chunk.html, is that each requires a more -complicated operation than simply summing and averaging over per-atom -values in each chunk. For example, many of them require calculation -of a center of mass, which requires summing mass*position over the -atoms and then dividing by summed mass. - -All of these computes produce a global vector or global array as -output, wih one or more values per chunk. They can be used -in various ways: - -As input to the "fix ave/time"_fix_ave_time.html command, which can -write the values to a file and optionally time average them. :ulb,l - -As input to the "fix ave/histo"_fix_ave_histo.html command to -histogram values across chunks. E.g. a histogram of cluster sizes or -molecule diffusion rates. :l - -As input to special functions of "equal-style -variables"_variable.html, like sum() and max(). E.g. to find the -largest cluster or fastest diffusing molecule. :l -:ule - -Example calculations with chunks :h4 - -Here are examples using chunk commands to calculate various -properties: - -(1) Average velocity in each of 1000 2d spatial bins: - -compute cc1 all chunk/atom bin/2d x 0.0 0.1 y lower 0.01 units reduced -fix 1 all ave/chunk 100 10 1000 cc1 vx vy file tmp.out :pre - -(2) Temperature in each spatial bin, after subtracting a flow -velocity: - -compute cc1 all chunk/atom bin/2d x 0.0 0.1 y lower 0.1 units reduced -compute vbias all temp/profile 1 0 0 y 10 -fix 1 all ave/chunk 100 10 1000 cc1 temp bias vbias file tmp.out :pre - -(3) Center of mass of each molecule: - -compute cc1 all chunk/atom molecule -compute myChunk all com/chunk cc1 -fix 1 all ave/time 100 1 100 c_myChunk\[*\] file tmp.out mode vector :pre - -(4) Total force on each molecule and ave/max across all molecules: - -compute cc1 all chunk/atom molecule -fix 1 all ave/chunk 1000 1 1000 cc1 fx fy fz file tmp.out -variable xave equal ave(f_1\[2\]) -variable xmax equal max(f_1\[2\]) -thermo 1000 -thermo_style custom step temp v_xave v_xmax :pre - -(5) Histogram of cluster sizes: - -compute cluster all cluster/atom 1.0 -compute cc1 all chunk/atom c_cluster compress yes -compute size all property/chunk cc1 count -fix 1 all ave/histo 100 1 100 0 20 20 c_size mode vector ave running beyond ignore file tmp.histo :pre - -:line - -6.24 Setting parameters for the "kspace_style pppm/disp"_kspace_style.html command :link(howto_24),h4 - -The PPPM method computes interactions by splitting the pair potential -into two parts, one of which is computed in a normal pairwise fashion, -the so-called real-space part, and one of which is computed using the -Fourier transform, the so called reciprocal-space or kspace part. For -both parts, the potential is not computed exactly but is approximated. -Thus, there is an error in both parts of the computation, the -real-space and the kspace error. The just mentioned facts are true -both for the PPPM for Coulomb as well as dispersion interactions. The -deciding difference - and also the reason why the parameters for -pppm/disp have to be selected with more care - is the impact of the -errors on the results: The kspace error of the PPPM for Coulomb and -dispersion interaction and the real-space error of the PPPM for -Coulomb interaction have the character of noise. In contrast, the -real-space error of the PPPM for dispersion has a clear physical -interpretation: the underprediction of cohesion. As a consequence, the -real-space error has a much stronger effect than the kspace error on -simulation results for pppm/disp. Parameters must thus be chosen in a -way that this error is much smaller than the kspace error. - -When using pppm/disp and not making any specifications on the PPPM -parameters via the kspace modify command, parameters will be tuned -such that the real-space error and the kspace error are equal. This -will result in simulations that are either inaccurate or slow, both of -which is not desirable. For selecting parameters for the pppm/disp -that provide fast and accurate simulations, there are two approaches, -which both have their up- and downsides. - -The first approach is to set desired real-space an kspace accuracies -via the {kspace_modify force/disp/real} and {kspace_modify -force/disp/kspace} commands. Note that the accuracies have to be -specified in force units and are thus dependent on the chosen unit -settings. For real units, 0.0001 and 0.002 seem to provide reasonable -accurate and efficient computations for the real-space and kspace -accuracies. 0.002 and 0.05 work well for most systems using lj -units. PPPM parameters will be generated based on the desired -accuracies. The upside of this approach is that it usually provides a -good set of parameters and will work for both the {kspace_modify diff -ad} and {kspace_modify diff ik} options. The downside of the method -is that setting the PPPM parameters will take some time during the -initialization of the simulation. - -The second approach is to set the parameters for the pppm/disp -explicitly using the {kspace_modify mesh/disp}, {kspace_modify -order/disp}, and {kspace_modify gewald/disp} commands. This approach -requires a more experienced user who understands well the impact of -the choice of parameters on the simulation accuracy and -performance. This approach provides a fast initialization of the -simulation. However, it is sensitive to errors: A combination of -parameters that will perform well for one system might result in -far-from-optimal conditions for other simulations. For example, -parameters that provide accurate and fast computations for -all-atomistic force fields can provide insufficient accuracy or -united-atomistic force fields (which is related to that the latter -typically have larger dispersion coefficients). - -To avoid inaccurate or inefficient simulations, the pppm/disp stops -simulations with an error message if no action is taken to control the -PPPM parameters. If the automatic parameter generation is desired and -real-space and kspace accuracies are desired to be equal, this error -message can be suppressed using the {kspace_modify disp/auto yes} -command. - -A reasonable approach that combines the upsides of both methods is to -make the first run using the {kspace_modify force/disp/real} and -{kspace_modify force/disp/kspace} commands, write down the PPPM -parameters from the outut, and specify these parameters using the -second approach in subsequent runs (which have the same composition, -force field, and approximately the same volume). - -Concerning the performance of the pppm/disp there are two more things -to consider. The first is that when using the pppm/disp, the cutoff -parameter does no longer affect the accuracy of the simulation -(subject to that gewald/disp is adjusted when changing the cutoff). -The performance can thus be increased by examining different values -for the cutoff parameter. A lower bound for the cutoff is only set by -the truncation error of the repulsive term of pair potentials. - -The second is that the mixing rule of the pair style has an impact on -the computation time when using the pppm/disp. Fastest computations -are achieved when using the geometric mixing rule. Using the -arithmetic mixing rule substantially increases the computational cost. -The computational overhead can be reduced using the {kspace_modify -mix/disp geom} and {kspace_modify splittol} commands. The first -command simply enforces geometric mixing of the dispersion -coefficients in kspace computations. This introduces some error in -the computations but will also significantly speed-up the -simulations. The second keyword sets the accuracy with which the -dispersion coefficients are approximated using a matrix factorization -approach. This may result in better accuracy then using the first -command, but will usually also not provide an equally good increase of -efficiency. - -Finally, pppm/disp can also be used when no mixing rules apply. -This can be achieved using the {kspace_modify mix/disp none} command. -Note that the code does not check automatically whether any mixing -rule is fulfilled. If mixing rules do not apply, the user will have -to specify this command explicitly. - -:line - -6.25 Polarizable models :link(howto_25),h4 - -In polarizable force fields the charge distributions in molecules and -materials respond to their electrostatic environments. Polarizable -systems can be simulated in LAMMPS using three methods: - -the fluctuating charge method, implemented in the "QEQ"_fix_qeq.html -package, :ulb,l -the adiabatic core-shell method, implemented in the -"CORESHELL"_#howto_26 package, :l -the thermalized Drude dipole method, implemented in the -"USER-DRUDE"_#howto_27 package. :l -:ule - -The fluctuating charge method calculates instantaneous charges on -interacting atoms based on the electronegativity equalization -principle. It is implemented in the "fix qeq"_fix_qeq.html which is -available in several variants. It is a relatively efficient technique -since no additional particles are introduced. This method allows for -charge transfer between molecules or atom groups. However, because the -charges are located at the interaction sites, off-plane components of -polarization cannot be represented in planar molecules or atom groups. - -The two other methods share the same basic idea: polarizable atoms are -split into one core atom and one satellite particle (called shell or -Drude particle) attached to it by a harmonic spring. Both atoms bear -a charge and they represent collectively an induced electric dipole. -These techniques are computationally more expensive than the QEq -method because of additional particles and bonds. These two -charge-on-spring methods differ in certain features, with the -core-shell model being normally used for ionic/crystalline materials, -whereas the so-called Drude model is normally used for molecular -systems and fluid states. - -The core-shell model is applicable to crystalline materials where the -high symmetry around each site leads to stable trajectories of the -core-shell pairs. However, bonded atoms in molecules can be so close -that a core would interact too strongly or even capture the Drude -particle of a neighbor. The Drude dipole model is relatively more -complex in order to remediate this and other issues. Specifically, the -Drude model includes specific thermostating of the core-Drude pairs -and short-range damping of the induced dipoles. - -The three polarization methods can be implemented through a -self-consistent calculation of charges or induced dipoles at each -timestep. In the fluctuating charge scheme this is done by the matrix -inversion method in "fix qeq/point"_fix_qeq.html, but for core-shell -or Drude-dipoles the relaxed-dipoles technique would require an slow -iterative procedure. These self-consistent solutions yield accurate -trajectories since the additional degrees of freedom representing -polarization are massless. An alternative is to attribute a mass to -the additional degrees of freedom and perform time integration using -an extended Lagrangian technique. For the fluctuating charge scheme -this is done by "fix qeq/dynamic"_fix_qeq.html, and for the -charge-on-spring models by the methods outlined in the next two -sections. The assignment of masses to the additional degrees of -freedom can lead to unphysical trajectories if care is not exerted in -choosing the parameters of the polarizable models and the simulation -conditions. - -In the core-shell model the vibration of the shells is kept faster -than the ionic vibrations to mimic the fast response of the -polarizable electrons. But in molecular systems thermalizing the -core-Drude pairs at temperatures comparable to the rest of the -simulation leads to several problems (kinetic energy transfer, too -short a timestep, etc.) In order to avoid these problems the relative -motion of the Drude particles with respect to their cores is kept -"cold" so the vibration of the core-Drude pairs is very slow, -approaching the self-consistent regime. In both models the -temperature is regulated using the velocities of the center of mass of -core+shell (or Drude) pairs, but in the Drude model the actual -relative core-Drude particle motion is thermostated separately as -well. - -:line - -6.26 Adiabatic core/shell model :link(howto_26),h4 - -The adiabatic core-shell model by "Mitchell and -Fincham"_#MitchellFincham is a simple method for adding -polarizability to a system. In order to mimic the electron shell of -an ion, a satellite particle is attached to it. This way the ions are -split into a core and a shell where the latter is meant to react to -the electrostatic environment inducing polarizability. - -Technically, shells are attached to the cores by a spring force f = -k*r where k is a parametrized spring constant and r is the distance -between the core and the shell. The charges of the core and the shell -add up to the ion charge, thus q(ion) = q(core) + q(shell). This -setup introduces the ion polarizability (alpha) given by -alpha = q(shell)^2 / k. In a -similar fashion the mass of the ion is distributed on the core and the -shell with the core having the larger mass. - -To run this model in LAMMPS, "atom_style"_atom_style.html {full} can -be used since atom charge and bonds are needed. Each kind of -core/shell pair requires two atom types and a bond type. The core and -shell of a core/shell pair should be bonded to each other with a -harmonic bond that provides the spring force. For example, a data file -for NaCl, as found in examples/coreshell, has this format: - -432 atoms # core and shell atoms -216 bonds # number of core/shell springs :pre - -4 atom types # 2 cores and 2 shells for Na and Cl -2 bond types :pre - -0.0 24.09597 xlo xhi -0.0 24.09597 ylo yhi -0.0 24.09597 zlo zhi :pre - -Masses # core/shell mass ratio = 0.1 :pre - -1 20.690784 # Na core -2 31.90500 # Cl core -3 2.298976 # Na shell -4 3.54500 # Cl shell :pre - -Atoms :pre - -1 1 2 1.5005 0.00000000 0.00000000 0.00000000 # core of core/shell pair 1 -2 1 4 -2.5005 0.00000000 0.00000000 0.00000000 # shell of core/shell pair 1 -3 2 1 1.5056 4.01599500 4.01599500 4.01599500 # core of core/shell pair 2 -4 2 3 -0.5056 4.01599500 4.01599500 4.01599500 # shell of core/shell pair 2 -(...) :pre - -Bonds # Bond topology for spring forces :pre - -1 2 1 2 # spring for core/shell pair 1 -2 2 3 4 # spring for core/shell pair 2 -(...) :pre - -Non-Coulombic (e.g. Lennard-Jones) pairwise interactions are only -defined between the shells. Coulombic interactions are defined -between all cores and shells. If desired, additional bonds can be -specified between cores. - -The "special_bonds"_special_bonds.html command should be used to -turn-off the Coulombic interaction within core/shell pairs, since that -interaction is set by the bond spring. This is done using the -"special_bonds"_special_bonds.html command with a 1-2 weight = 0.0, -which is the default value. It needs to be considered whether one has -to adjust the "special_bonds"_special_bonds.html weighting according -to the molecular topology since the interactions of the shells are -bypassed over an extra bond. - -Note that this core/shell implementation does not require all ions to -be polarized. One can mix core/shell pairs and ions without a -satellite particle if desired. - -Since the core/shell model permits distances of r = 0.0 between the -core and shell, a pair style with a "cs" suffix needs to be used to -implement a valid long-range Coulombic correction. Several such pair -styles are provided in the CORESHELL package. See "this doc -page"_pair_cs.html for details. All of the core/shell enabled pair -styles require the use of a long-range Coulombic solver, as specified -by the "kspace_style"_kspace_style.html command. Either the PPPM or -Ewald solvers can be used. - -For the NaCL example problem, these pair style and bond style settings -are used: - -pair_style born/coul/long/cs 20.0 20.0 -pair_coeff * * 0.0 1.000 0.00 0.00 0.00 -pair_coeff 3 3 487.0 0.23768 0.00 1.05 0.50 #Na-Na -pair_coeff 3 4 145134.0 0.23768 0.00 6.99 8.70 #Na-Cl -pair_coeff 4 4 405774.0 0.23768 0.00 72.40 145.40 #Cl-Cl :pre - -bond_style harmonic -bond_coeff 1 63.014 0.0 -bond_coeff 2 25.724 0.0 :pre - -When running dynamics with the adiabatic core/shell model, the -following issues should be considered. The relative motion of -the core and shell particles corresponds to the polarization, -hereby an instantaneous relaxation of the shells is approximated -and a fast core/shell spring frequency ensures a nearly constant -internal kinetic energy during the simulation. -Thermostats can alter this polarization behaviour, by scaling the -internal kinetic energy, meaning the shell will not react freely to -its electrostatic environment. -Therefore it is typically desirable to decouple the relative motion of -the core/shell pair, which is an imaginary degree of freedom, from the -real physical system. To do that, the "compute -temp/cs"_compute_temp_cs.html command can be used, in conjunction with -any of the thermostat fixes, such as "fix nvt"_fix_nh.html or "fix -langevin"_fix_langevin. This compute uses the center-of-mass velocity -of the core/shell pairs to calculate a temperature, and insures that -velocity is what is rescaled for thermostatting purposes. This -compute also works for a system with both core/shell pairs and -non-polarized ions (ions without an attached satellite particle). The -"compute temp/cs"_compute_temp_cs.html command requires input of two -groups, one for the core atoms, another for the shell atoms. -Non-polarized ions which might also be included in the treated system -should not be included into either of these groups, they are taken -into account by the {group-ID} (2nd argument) of the compute. The -groups can be defined using the "group {type}"_group.html command. -Note that to perform thermostatting using this definition of -temperature, the "fix modify temp"_fix_modify.html command should be -used to assign the compute to the thermostat fix. Likewise the -"thermo_modify temp"_thermo_modify.html command can be used to make -this temperature be output for the overall system. - -For the NaCl example, this can be done as follows: - -group cores type 1 2 -group shells type 3 4 -compute CSequ all temp/cs cores shells -fix thermoberendsen all temp/berendsen 1427 1427 0.4 # thermostat for the true physical system -fix thermostatequ all nve # integrator as needed for the berendsen thermostat -fix_modify thermoberendsen temp CSequ -thermo_modify temp CSequ # output of center-of-mass derived temperature :pre - -The pressure for the core/shell system is computed via the regular -LAMMPS convention by "treating the cores and shells as individual -particles"_#MitchellFincham2. For the thermo output of the pressure -as well as for the application of a barostat, it is necessary to -use an additional "pressure"_compute_pressure compute based on the -default "temperature"_compute_temp and specifying it as a second -argument in "fix modify"_fix_modify.html and -"thermo_modify"_thermo_modify.html resulting in: - -(...) -compute CSequ all temp/cs cores shells -compute thermo_press_lmp all pressure thermo_temp # pressure for individual particles -thermo_modify temp CSequ press thermo_press_lmp # modify thermo to regular pressure -fix press_bar all npt temp 300 300 0.04 iso 0 0 0.4 -fix_modify press_bar temp CSequ press thermo_press_lmp # pressure modification for correct kinetic scalar :pre - -If "compute temp/cs"_compute_temp_cs.html is used, the decoupled -relative motion of the core and the shell should in theory be -stable. However numerical fluctuation can introduce a small -momentum to the system, which is noticable over long trajectories. -Therefore it is recommendable to use the "fix -momentum"_fix_momentum.html command in combination with "compute -temp/cs"_compute_temp_cs.html when equilibrating the system to -prevent any drift. - -When initializing the velocities of a system with core/shell pairs, it -is also desirable to not introduce energy into the relative motion of -the core/shell particles, but only assign a center-of-mass velocity to -the pairs. This can be done by using the {bias} keyword of the -"velocity create"_velocity.html command and assigning the "compute -temp/cs"_compute_temp_cs.html command to the {temp} keyword of the -"velocity"_velocity.html command, e.g. - -velocity all create 1427 134 bias yes temp CSequ -velocity all scale 1427 temp CSequ :pre - -To maintain the correct polarizability of the core/shell pairs, the -kinetic energy of the internal motion shall remain nearly constant. -Therefore the choice of spring force and mass ratio need to ensure -much faster relative motion of the 2 atoms within the core/shell pair -than their center-of-mass velocity. This allows the shells to -effectively react instantaneously to the electrostatic environment and -limits energy transfer to or from the core/shell oscillators. -This fast movement also dictates the timestep that can be used. - -The primary literature of the adiabatic core/shell model suggests that -the fast relative motion of the core/shell pairs only allows negligible -energy transfer to the environment. -The mentioned energy transfer will typically lead to a small drift -in total energy over time. This internal energy can be monitored -using the "compute chunk/atom"_compute_chunk_atom.html and "compute -temp/chunk"_compute_temp_chunk.html commands. The internal kinetic -energies of each core/shell pair can then be summed using the sum() -special function of the "variable"_variable.html command. Or they can -be time/averaged and output using the "fix ave/time"_fix_ave_time.html -command. To use these commands, each core/shell pair must be defined -as a "chunk". If each core/shell pair is defined as its own molecule, -the molecule ID can be used to define the chunks. If cores are bonded -to each other to form larger molecules, the chunks can be identified -by the "fix property/atom"_fix_property_atom.html via assigning a -core/shell ID to each atom using a special field in the data file read -by the "read_data"_read_data.html command. This field can then be -accessed by the "compute property/atom"_compute_property_atom.html -command, to use as input to the "compute -chunk/atom"_compute_chunk_atom.html command to define the core/shell -pairs as chunks. - -For example if core/shell pairs are the only molecules: - -read_data NaCl_CS_x0.1_prop.data -compute prop all property/atom molecule -compute cs_chunk all chunk/atom c_prop -compute cstherm all temp/chunk cs_chunk temp internal com yes cdof 3.0 # note the chosen degrees of freedom for the core/shell pairs -fix ave_chunk all ave/time 10 1 10 c_cstherm file chunk.dump mode vector :pre - -For example if core/shell pairs and other molecules are present: - -fix csinfo all property/atom i_CSID # property/atom command -read_data NaCl_CS_x0.1_prop.data fix csinfo NULL CS-Info # atom property added in the data-file -compute prop all property/atom i_CSID -(...) :pre - -The additional section in the date file would be formatted like this: - -CS-Info # header of additional section :pre - -1 1 # column 1 = atom ID, column 2 = core/shell ID -2 1 -3 2 -4 2 -5 3 -6 3 -7 4 -8 4 -(...) :pre - -:line - -6.27 Drude induced dipoles :link(howto_27),h4 - -The thermalized Drude model, similarly to the "core-shell"_#howto_26 -model, represents induced dipoles by a pair of charges (the core atom -and the Drude particle) connected by a harmonic spring. The Drude -model has a number of features aimed at its use in molecular systems -("Lamoureux and Roux"_#howto-Lamoureux): - -Thermostating of the additional degrees of freedom associated with the -induced dipoles at very low temperature, in terms of the reduced -coordinates of the Drude particles with respect to their cores. This -makes the trajectory close to that of relaxed induced dipoles. :ulb,l - -Consistent definition of 1-2 to 1-4 neighbors. A core-Drude particle -pair represents a single (polarizable) atom, so the special screening -factors in a covalent structure should be the same for the core and -the Drude particle. Drude particles have to inherit the 1-2, 1-3, 1-4 -special neighbor relations from their respective cores. :l - -Stabilization of the interactions between induced dipoles. Drude -dipoles on covalently bonded atoms interact too strongly due to the -short distances, so an atom may capture the Drude particle of a -neighbor, or the induced dipoles within the same molecule may align -too much. To avoid this, damping at short range can be done by Thole -functions (for which there are physical grounds). This Thole damping -is applied to the point charges composing the induced dipole (the -charge of the Drude particle and the opposite charge on the core, not -to the total charge of the core atom). :l -:ule - -A detailed tutorial covering the usage of Drude induced dipoles in -LAMMPS is "available here"_tutorial_drude.html. - -As with the core-shell model, the cores and Drude particles should -appear in the data file as standard atoms. The same holds for the -springs between them, which are described by standard harmonic bonds. -The nature of the atoms (core, Drude particle or non-polarizable) is -specified via the "fix drude"_fix_drude.html command. The special -list of neighbors is automatically refactored to account for the -equivalence of core and Drude particles as regards special 1-2 to 1-4 -screening. It may be necessary to use the {extra/special/per/atom} -keyword of the "read_data"_read_data.html command. If using "fix -shake"_fix_shake.html, make sure no Drude particle is in this fix -group. - -There are two ways to thermostat the Drude particles at a low -temperature: use either "fix langevin/drude"_fix_langevin_drude.html -for a Langevin thermostat, or "fix -drude/transform/*"_fix_drude_transform.html for a Nose-Hoover -thermostat. The former requires use of the command "comm_modify vel -yes"_comm_modify.html. The latter requires two separate integration -fixes like {nvt} or {npt}. The correct temperatures of the reduced -degrees of freedom can be calculated using the "compute -temp/drude"_compute_temp_drude.html. This requires also to use the -command {comm_modify vel yes}. - -Short-range damping of the induced dipole interactions can be achieved -using Thole functions through the "pair style -thole"_pair_thole.html in "pair_style hybrid/overlay"_pair_hybrid.html -with a Coulomb pair style. It may be useful to use {coul/long/cs} or -similar from the CORESHELL package if the core and Drude particle come -too close, which can cause numerical issues. - -:line - -6.28 Magnetic spins :link(howto_28),h4 - -Classical magnetic spin simualtions can be performed via the SPIN -package. The algrorithmic and implementation details are described in -"Tranchida"_#Tranchida7. - -The model representents the simulation of atomic magnetic spins -coupled to lattice vibrations. The dynamics of those magnetic spins -can be used to simulate a broad range a phenomena related to -magneto-elasticity, or or to study the influence of defects on the -magnetic properties of materials. - -The magnetic spins are interacting with each others and with the -lattice via pair interactions. Typically, the magnetic exchange -interaction can be defined using the -"pair/spin/exchange"_pair_spin_exchange.html command. This exchange -applies a magnetic torque to a given spin, considering the orientation -of its neighboring spins and their relative distances. -It also applies a force on the atoms as a function of the spin -orientations and their associated inter-atomic distances. - -The command "fix precession/spin"_fix_precession_spin.html allows to -apply a constant magnetic torque on all the spins in the system. This -torque can be an external magnetic field (Zeeman interaction), or an -uniaxial magnetic anisotropy. - -A Langevin thermostat can be applied to those magnetic spins using -"fix langevin/spin"_fix_langevin_spin.html. Typically, this thermostat -can be coupled to another Langevin thermostat applied to the atoms -using "fix langevin"_fix_langevin.html in order to simulate -thermostated spin-lattice system. - -The magnetic Gilbert damping can also be applied using "fix -langevin/spin"_fix_langevin_spin.html. It allows to either dissipate -the thermal energy of the Langevin thermostat, or to perform a -relaxation of the magnetic configuration toward an equilibrium state. - -All the computed magnetic properties can be outputed by two main -commands. The first one is "compute spin"_compute_spin.html, that -enables to evaluate magnetic averaged quantities, such as the total -magnetization of the system along x, y, or z, the spin temperature, or -the magnetic energy. The second command is "compute -property/atom"_compute_property_atom.html. It enables to output all the -per atom magnetic quantities. Typically, the orientation of a given -magnetic spin, or the magnetic force acting on this spin. - -:line -:line - -:link(howto-Berendsen) -[(Berendsen)] Berendsen, Grigera, Straatsma, J Phys Chem, 91, -6269-6271 (1987). - -:link(howto-Cornell) -[(Cornell)] Cornell, Cieplak, Bayly, Gould, Merz, Ferguson, -Spellmeyer, Fox, Caldwell, Kollman, JACS 117, 5179-5197 (1995). - -:link(Horn) -[(Horn)] Horn, Swope, Pitera, Madura, Dick, Hura, and Head-Gordon, -J Chem Phys, 120, 9665 (2004). - -:link(howto-Ikeshoji) -[(Ikeshoji)] Ikeshoji and Hafskjold, Molecular Physics, 81, 251-261 -(1994). - -:link(howto-Wirnsberger) -[(Wirnsberger)] Wirnsberger, Frenkel, and Dellago, J Chem Phys, 143, 124104 -(2015). - -:link(howto-MacKerell) -[(MacKerell)] MacKerell, Bashford, Bellott, Dunbrack, Evanseck, Field, -Fischer, Gao, Guo, Ha, et al, J Phys Chem, 102, 3586 (1998). - -:link(howto-Mayo) -[(Mayo)] Mayo, Olfason, Goddard III, J Phys Chem, 94, 8897-8909 -(1990). - -:link(Jorgensen1) -[(Jorgensen)] Jorgensen, Chandrasekhar, Madura, Impey, Klein, J Chem -Phys, 79, 926 (1983). - -:link(Price1) -[(Price)] Price and Brooks, J Chem Phys, 121, 10096 (2004). - -:link(Shinoda1) -[(Shinoda)] Shinoda, Shiga, and Mikami, Phys Rev B, 69, 134103 (2004). - -:link(MitchellFincham) -[(Mitchell and Fincham)] Mitchell, Fincham, J Phys Condensed Matter, -5, 1031-1038 (1993). - -:link(MitchellFincham2) -[(Fincham)] Fincham, Mackrodt and Mitchell, J Phys Condensed Matter, -6, 393-404 (1994). - -:link(howto-Lamoureux) -[(Lamoureux and Roux)] G. Lamoureux, B. Roux, J. Chem. Phys 119, 3025 (2003) - -:link(Tranchida7) -[(Tranchida)] Tranchida, Plimpton, Thibaudeau and Thompson, -arXiv preprint arXiv:1801.10233, (2018). diff --git a/doc/src/Section_intro.txt b/doc/src/Section_intro.txt deleted file mode 100644 index 36a1181ca7..0000000000 --- a/doc/src/Section_intro.txt +++ /dev/null @@ -1,550 +0,0 @@ -"Previous Section"_Manual.html - "LAMMPS WWW Site"_lws - "LAMMPS -Documentation"_ld - "LAMMPS Commands"_lc - "Next -Section"_Section_start.html :c - -:link(lws,http://lammps.sandia.gov) -:link(ld,Manual.html) -:link(lc,Section_commands.html#comm) - -:line - -1. Introduction :h2 - -This section provides an overview of what LAMMPS can and can't do, -describes what it means for LAMMPS to be an open-source code, and -acknowledges the funding and people who have contributed to LAMMPS -over the years. - -1.1 "What is LAMMPS"_#intro_1 -1.2 "LAMMPS features"_#intro_2 -1.3 "LAMMPS non-features"_#intro_3 -1.4 "Open source distribution"_#intro_4 -1.5 "Acknowledgments and citations"_#intro_5 :all(b) - -:line -:line - -1.1 What is LAMMPS :link(intro_1),h4 - -LAMMPS is a classical molecular dynamics code that models an ensemble -of particles in a liquid, solid, or gaseous state. It can model -atomic, polymeric, biological, metallic, granular, and coarse-grained -systems using a variety of force fields and boundary conditions. - -For examples of LAMMPS simulations, see the Publications page of the -"LAMMPS WWW Site"_lws. - -LAMMPS runs efficiently on single-processor desktop or laptop -machines, but is designed for parallel computers. It will run on any -parallel machine that compiles C++ and supports the "MPI"_mpi -message-passing library. This includes distributed- or shared-memory -parallel machines and Beowulf-style clusters. - -:link(mpi,http://www-unix.mcs.anl.gov/mpi) - -LAMMPS can model systems with only a few particles up to millions or -billions. See "Section 8"_Section_perf.html for information on -LAMMPS performance and scalability, or the Benchmarks section of the -"LAMMPS WWW Site"_lws. - -LAMMPS is a freely-available open-source code, distributed under the -terms of the "GNU Public License"_gnu, which means you can use or -modify the code however you wish. See "this section"_#intro_4 for a -brief discussion of the open-source philosophy. - -:link(gnu,http://www.gnu.org/copyleft/gpl.html) - -LAMMPS is designed to be easy to modify or extend with new -capabilities, such as new force fields, atom types, boundary -conditions, or diagnostics. See the "Modify"_Modify.html doc page for -more details. - -The current version of LAMMPS is written in C++. Earlier versions -were written in F77 and F90. See -"Section 13"_Section_history.html for more information on -different versions. All versions can be downloaded from the "LAMMPS -WWW Site"_lws. - -LAMMPS was originally developed under a US Department of Energy CRADA -(Cooperative Research and Development Agreement) between two DOE labs -and 3 companies. It is distributed by "Sandia National Labs"_snl. -See "this section"_#intro_5 for more information on LAMMPS funding and -individuals who have contributed to LAMMPS. - -:link(snl,http://www.sandia.gov) - -In the most general sense, LAMMPS integrates Newton's equations of -motion for collections of atoms, molecules, or macroscopic particles -that interact via short- or long-range forces with a variety of -initial and/or boundary conditions. For computational efficiency -LAMMPS uses neighbor lists to keep track of nearby particles. The -lists are optimized for systems with particles that are repulsive at -short distances, so that the local density of particles never becomes -too large. On parallel machines, LAMMPS uses spatial-decomposition -techniques to partition the simulation domain into small 3d -sub-domains, one of which is assigned to each processor. Processors -communicate and store "ghost" atom information for atoms that border -their sub-domain. LAMMPS is most efficient (in a parallel sense) for -systems whose particles fill a 3d rectangular box with roughly uniform -density. Papers with technical details of the algorithms used in -LAMMPS are listed in "this section"_#intro_5. - -:line - -1.2 LAMMPS features :link(intro_2),h4 - -This section highlights LAMMPS features, with pointers to specific -commands which give more details. If LAMMPS doesn't have your -favorite interatomic potential, boundary condition, or atom type, see -the "Modify"_Modify.html doc page, which describes how you can add it -to LAMMPS. - -General features :h4 - - runs on a single processor or in parallel - distributed-memory message-passing parallelism (MPI) - spatial-decomposition of simulation domain for parallelism - open-source distribution - highly portable C++ - optional libraries used: MPI and single-processor FFT - GPU (CUDA and OpenCL), Intel(R) Xeon Phi(TM) coprocessors, and OpenMP support for many code features - easy to extend with new features and functionality - runs from an input script - syntax for defining and using variables and formulas - syntax for looping over runs and breaking out of loops - run one or multiple simulations simultaneously (in parallel) from one script - build as library, invoke LAMMPS thru library interface or provided Python wrapper - couple with other codes: LAMMPS calls other code, other code calls LAMMPS, umbrella code calls both :ul - -Particle and model types :h4 -("atom style"_atom_style.html command) - - atoms - coarse-grained particles (e.g. bead-spring polymers) - united-atom polymers or organic molecules - all-atom polymers, organic molecules, proteins, DNA - metals - granular materials - coarse-grained mesoscale models - finite-size spherical and ellipsoidal particles - finite-size line segment (2d) and triangle (3d) particles - point dipole particles - rigid collections of particles - hybrid combinations of these :ul - -Force fields :h4 -("pair style"_pair_style.html, "bond style"_bond_style.html, -"angle style"_angle_style.html, "dihedral style"_dihedral_style.html, -"improper style"_improper_style.html, "kspace style"_kspace_style.html -commands) - - pairwise potentials: Lennard-Jones, Buckingham, Morse, Born-Mayer-Huggins, \ - Yukawa, soft, class 2 (COMPASS), hydrogen bond, tabulated - charged pairwise potentials: Coulombic, point-dipole - manybody potentials: EAM, Finnis/Sinclair EAM, modified EAM (MEAM), \ - embedded ion method (EIM), EDIP, ADP, Stillinger-Weber, Tersoff, \ - REBO, AIREBO, ReaxFF, COMB, SNAP, Streitz-Mintmire, 3-body polymorphic - long-range interactions for charge, point-dipoles, and LJ dispersion: \ - Ewald, Wolf, PPPM (similar to particle-mesh Ewald) - polarization models: "QEq"_fix_qeq.html, \ - "core/shell model"_Section_howto.html#howto_26, \ - "Drude dipole model"_Section_howto.html#howto_27 - charge equilibration (QEq via dynamic, point, shielded, Slater methods) - coarse-grained potentials: DPD, GayBerne, REsquared, colloidal, DLVO - mesoscopic potentials: granular, Peridynamics, SPH - electron force field (eFF, AWPMD) - bond potentials: harmonic, FENE, Morse, nonlinear, class 2, \ - quartic (breakable) - angle potentials: harmonic, CHARMM, cosine, cosine/squared, cosine/periodic, \ - class 2 (COMPASS) - dihedral potentials: harmonic, CHARMM, multi-harmonic, helix, \ - class 2 (COMPASS), OPLS - improper potentials: harmonic, cvff, umbrella, class 2 (COMPASS) - polymer potentials: all-atom, united-atom, bead-spring, breakable - water potentials: TIP3P, TIP4P, SPC - implicit solvent potentials: hydrodynamic lubrication, Debye - force-field compatibility with common CHARMM, AMBER, DREIDING, \ - OPLS, GROMACS, COMPASS options - access to "KIM archive"_http://openkim.org of potentials via \ - "pair kim"_pair_kim.html - hybrid potentials: multiple pair, bond, angle, dihedral, improper \ - potentials can be used in one simulation - overlaid potentials: superposition of multiple pair potentials :ul - -Atom creation :h4 -("read_data"_read_data.html, "lattice"_lattice.html, -"create_atoms"_create_atoms.html, "delete_atoms"_delete_atoms.html, -"displace_atoms"_displace_atoms.html, "replicate"_replicate.html commands) - - read in atom coords from files - create atoms on one or more lattices (e.g. grain boundaries) - delete geometric or logical groups of atoms (e.g. voids) - replicate existing atoms multiple times - displace atoms :ul - -Ensembles, constraints, and boundary conditions :h4 -("fix"_fix.html command) - - 2d or 3d systems - orthogonal or non-orthogonal (triclinic symmetry) simulation domains - constant NVE, NVT, NPT, NPH, Parinello/Rahman integrators - thermostatting options for groups and geometric regions of atoms - pressure control via Nose/Hoover or Berendsen barostatting in 1 to 3 dimensions - simulation box deformation (tensile and shear) - harmonic (umbrella) constraint forces - rigid body constraints - SHAKE bond and angle constraints - Monte Carlo bond breaking, formation, swapping - atom/molecule insertion and deletion - walls of various kinds - non-equilibrium molecular dynamics (NEMD) - variety of additional boundary conditions and constraints :ul - -Integrators :h4 -("run"_run.html, "run_style"_run_style.html, "minimize"_minimize.html commands) - - velocity-Verlet integrator - Brownian dynamics - rigid body integration - energy minimization via conjugate gradient or steepest descent relaxation - rRESPA hierarchical timestepping - rerun command for post-processing of dump files :ul - -Diagnostics :h4 - - see the various flavors of the "fix"_fix.html and "compute"_compute.html commands :ul - -Output :h4 -("dump"_dump.html, "restart"_restart.html commands) - - log file of thermodynamic info - text dump files of atom coords, velocities, other per-atom quantities - binary restart files - parallel I/O of dump and restart files - per-atom quantities (energy, stress, centro-symmetry parameter, CNA, etc) - user-defined system-wide (log file) or per-atom (dump file) calculations - spatial and time averaging of per-atom quantities - time averaging of system-wide quantities - atom snapshots in native, XYZ, XTC, DCD, CFG formats :ul - -Multi-replica models :h4 - -"nudged elastic band"_neb.html -"parallel replica dynamics"_prd.html -"temperature accelerated dynamics"_tad.html -"parallel tempering"_temper.html - -Pre- and post-processing :h4 - -Various pre- and post-processing serial tools are packaged with -LAMMPS; see the "Tools"_Tools.html doc page for details. :ulb,l - -Our group has also written and released a separate toolkit called -"Pizza.py"_pizza which provides tools for doing setup, analysis, -plotting, and visualization for LAMMPS simulations. Pizza.py is -written in "Python"_python and is available for download from "the -Pizza.py WWW site"_pizza. :l -:ule - -:link(pizza,http://www.sandia.gov/~sjplimp/pizza.html) -:link(python,http://www.python.org) - -Specialized features :h4 - -LAMMPS can be built with optional packages which implement a variety -of additional capabilities. An overview of all the packages is "given -here"_Packages.html. - -These are some LAMMPS capabilities which you may not think of as -typical classical molecular dynamics options: - -"static"_balance.html and "dynamic load-balancing"_fix_balance.html -"generalized aspherical particles"_body.html -"stochastic rotation dynamics (SRD)"_fix_srd.html -"real-time visualization and interactive MD"_fix_imd.html -calculate "virtual diffraction patterns"_compute_xrd.html -"atom-to-continuum coupling"_fix_atc.html with finite elements -coupled rigid body integration via the "POEMS"_fix_poems.html library -"QM/MM coupling"_fix_qmmm.html -"path-integral molecular dynamics (PIMD)"_fix_ipi.html and "this as well"_fix_pimd.html -Monte Carlo via "GCMC"_fix_gcmc.html and "tfMC"_fix_tfmc.html "atom swapping"_fix_atom_swap.html and "bond swapping"_fix_bond_swap.html -"Direct Simulation Monte Carlo"_pair_dsmc.html for low-density fluids -"Peridynamics mesoscale modeling"_pair_peri.html -"Lattice Boltzmann fluid"_fix_lb_fluid.html -"targeted"_fix_tmd.html and "steered"_fix_smd.html molecular dynamics -"two-temperature electron model"_fix_ttm.html :ul - -:line - -1.3 LAMMPS non-features :link(intro_3),h4 - -LAMMPS is designed to efficiently compute Newton's equations of motion -for a system of interacting particles. Many of the tools needed to -pre- and post-process the data for such simulations are not included -in the LAMMPS kernel for several reasons: - -the desire to keep LAMMPS simple -they are not parallel operations -other codes already do them -limited development resources :ul - -Specifically, LAMMPS itself does not: - -run thru a GUI -build molecular systems -assign force-field coefficients automagically -perform sophisticated analyses of your MD simulation -visualize your MD simulation -plot your output data :ul - -A few tools for pre- and post-processing tasks are provided as part of -the LAMMPS package; they are described on the "Tools"_Tools.html doc -page. However, many people use other codes or write their own tools -for these tasks. - -As noted above, our group has also written and released a separate -toolkit called "Pizza.py"_pizza which addresses some of the listed -bullets. It provides tools for doing setup, analysis, plotting, and -visualization for LAMMPS simulations. Pizza.py is written in -"Python"_python and is available for download from "the Pizza.py WWW -site"_pizza. - -LAMMPS requires as input a list of initial atom coordinates and types, -molecular topology information, and force-field coefficients assigned -to all atoms and bonds. LAMMPS will not build molecular systems and -assign force-field parameters for you. - -For atomic systems LAMMPS provides a "create_atoms"_create_atoms.html -command which places atoms on solid-state lattices (fcc, bcc, -user-defined, etc). Assigning small numbers of force field -coefficients can be done via the "pair coeff"_pair_coeff.html, "bond -coeff"_bond_coeff.html, "angle coeff"_angle_coeff.html, etc commands. -For molecular systems or more complicated simulation geometries, users -typically use another code as a builder and convert its output to -LAMMPS input format, or write their own code to generate atom -coordinate and molecular topology for LAMMPS to read in. - -For complicated molecular systems (e.g. a protein), a multitude of -topology information and hundreds of force-field coefficients must -typically be specified. We suggest you use a program like -"CHARMM"_charmm or "AMBER"_amber or other molecular builders to setup -such problems and dump its information to a file. You can then -reformat the file as LAMMPS input. Some of the tools described on the -"Tools"_Tools.html doc page can assist in this process. - -Similarly, LAMMPS creates output files in a simple format. Most users -post-process these files with their own analysis tools or re-format -them for input into other programs, including visualization packages. -If you are convinced you need to compute something on-the-fly as -LAMMPS runs, see the "Modify"_Modify.html doc page for a discussion of -how you can use the "dump"_dump.html and "compute"_compute.html and -"fix"_fix.html commands to print out data of your choosing. Keep in -mind that complicated computations can slow down the molecular -dynamics timestepping, particularly if the computations are not -parallel, so it is often better to leave such analysis to -post-processing codes. - -For high-quality visualization we recommend the -following packages: - -"VMD"_http://www.ks.uiuc.edu/Research/vmd -"AtomEye"_http://mt.seas.upenn.edu/Archive/Graphics/A -"OVITO"_http://www.ovito.org/ -"ParaView"_http://www.paraview.org/ -"PyMol"_http://www.pymol.org -"Raster3d"_http://www.bmsc.washington.edu/raster3d/raster3d.html -"RasMol"_http://www.openrasmol.org :ul - -Other features that LAMMPS does not yet (and may never) support are -discussed in "Section 13"_Section_history.html. - -Finally, these are freely-available molecular dynamics codes, most of -them parallel, which may be well-suited to the problems you want to -model. They can also be used in conjunction with LAMMPS to perform -complementary modeling tasks. - -"CHARMM"_charmm -"AMBER"_amber -"NAMD"_namd -"NWCHEM"_nwchem -"DL_POLY"_dlpoly -"Tinker"_tinker :ul - -:link(charmm,http://www.charmm.org) -:link(amber,http://ambermd.org) -:link(namd,http://www.ks.uiuc.edu/Research/namd/) -:link(nwchem,http://www.emsl.pnl.gov/docs/nwchem/nwchem.html) -:link(dlpoly,http://www.ccp5.ac.uk/DL_POLY_CLASSIC) -:link(tinker,http://dasher.wustl.edu/tinker) - -CHARMM, AMBER, NAMD, NWCHEM, and Tinker are designed primarily for -modeling biological molecules. CHARMM and AMBER use -atom-decomposition (replicated-data) strategies for parallelism; NAMD -and NWCHEM use spatial-decomposition approaches, similar to LAMMPS. -Tinker is a serial code. DL_POLY includes potentials for a variety of -biological and non-biological materials; both a replicated-data and -spatial-decomposition version exist. - -:line - -1.4 Open source distribution :link(intro_4),h4 - -LAMMPS comes with no warranty of any kind. As each source file states -in its header, it is a copyrighted code that is distributed free-of- -charge, under the terms of the "GNU Public License"_gnu (GPL). This -is often referred to as open-source distribution - see -"www.gnu.org"_gnuorg or "www.opensource.org"_opensource for more -details. The legal text of the GPL is in the LICENSE file that is -included in the LAMMPS distribution. - -:link(gnuorg,http://www.gnu.org) -:link(opensource,http://www.opensource.org) - -Here is a summary of what the GPL means for LAMMPS users: - -(1) Anyone is free to use, modify, or extend LAMMPS in any way they -choose, including for commercial purposes. - -(2) If you distribute a modified version of LAMMPS, it must remain -open-source, meaning you distribute it under the terms of the GPL. -You should clearly annotate such a code as a derivative version of -LAMMPS. - -(3) If you release any code that includes LAMMPS source code, then it -must also be open-sourced, meaning you distribute it under the terms -of the GPL. - -(4) If you give LAMMPS files to someone else, the GPL LICENSE file and -source file headers (including the copyright and GPL notices) should -remain part of the code. - -In the spirit of an open-source code, these are various ways you can -contribute to making LAMMPS better. You can send email to the -"developers"_http://lammps.sandia.gov/authors.html on any of these -items. - -Point prospective users to the "LAMMPS WWW Site"_lws. Mention it in -talks or link to it from your WWW site. :ulb,l - -If you find an error or omission in this manual or on the "LAMMPS WWW -Site"_lws, or have a suggestion for something to clarify or include, -send an email to the -"developers"_http://lammps.sandia.gov/authors.html. :l - -If you find a bug, the "Errors bugs"_Errors_bugs.html doc page -describes how to report it. :l - -If you publish a paper using LAMMPS results, send the citation (and -any cool pictures or movies if you like) to add to the Publications, -Pictures, and Movies pages of the "LAMMPS WWW Site"_lws, with links -and attributions back to you. :l - -Create a new Makefile.machine that can be added to the src/MAKE -directory. :l - -The tools sub-directory of the LAMMPS distribution has various -stand-alone codes for pre- and post-processing of LAMMPS data. More -details are given on the "Tools"_Tools.html doc page. If you write a -new tool that users will find useful, it can be added to the LAMMPS -distribution. :l - -LAMMPS is designed to be easy to extend with new code for features -like potentials, boundary conditions, diagnostic computations, etc. -The "Modify"_Modify.html doc page gives details. If you add a feature -of general interest, it can be added to the LAMMPS distribution. :l - -The Benchmark page of the "LAMMPS WWW Site"_lws lists LAMMPS -performance on various platforms. The files needed to run the -benchmarks are part of the LAMMPS distribution. If your machine is -sufficiently different from those listed, your timing data can be -added to the page. :l - -You can send feedback for the User Comments page of the "LAMMPS WWW -Site"_lws. It might be added to the page. No promises. :l - -Cash. Small denominations, unmarked bills preferred. Paper sack OK. -Leave on desk. VISA also accepted. Chocolate chip cookies -encouraged. :l -:ule - -:line - -1.5 Acknowledgments and citations :h3,link(intro_5) - -LAMMPS development has been funded by the "US Department of -Energy"_doe (DOE), through its CRADA, LDRD, ASCI, and Genomes-to-Life -programs and its "OASCR"_oascr and "OBER"_ober offices. - -Specifically, work on the latest version was funded in part by the US -Department of Energy's Genomics:GTL program -("www.doegenomestolife.org"_gtl) under the "project"_ourgtl, "Carbon -Sequestration in Synechococcus Sp.: From Molecular Machines to -Hierarchical Modeling". - -:link(doe,http://www.doe.gov) -:link(gtl,http://www.doegenomestolife.org) -:link(ourgtl,http://www.genomes2life.org) -:link(oascr,http://www.sc.doe.gov/ascr/home.html) -:link(ober,http://www.er.doe.gov/production/ober/ober_top.html) - -The following paper describe the basic parallel algorithms used in -LAMMPS. If you use LAMMPS results in your published work, please cite -this paper and include a pointer to the "LAMMPS WWW Site"_lws -(http://lammps.sandia.gov): - -S. Plimpton, [Fast Parallel Algorithms for Short-Range Molecular -Dynamics], J Comp Phys, 117, 1-19 (1995). - -Other papers describing specific algorithms used in LAMMPS are listed -under the "Citing LAMMPS link"_http://lammps.sandia.gov/cite.html of -the LAMMPS WWW page. - -The "Publications link"_http://lammps.sandia.gov/papers.html on the -LAMMPS WWW page lists papers that have cited LAMMPS. If your paper is -not listed there for some reason, feel free to send us the info. If -the simulations in your paper produced cool pictures or animations, -we'll be pleased to add them to the -"Pictures"_http://lammps.sandia.gov/pictures.html or -"Movies"_http://lammps.sandia.gov/movies.html pages of the LAMMPS WWW -site. - -The primary LAMMPS developers are at Sandia National Labs and Temple University: - -Steve Plimpton, sjplimp at sandia.gov -Aidan Thompson, athomps at sandia.gov -Stan Moore, stamoor at sandia.gov -Axel Kohlmeyer, akohlmey at gmail.com :ul - -Past primary developers include Paul Crozier and Mark Stevens, -both at Sandia, and Ray Shan, now at Materials Design. - -The following folks are responsible for significant contributions to -the code, or other aspects of the LAMMPS development effort. Many of -the packages they have written are somewhat unique to LAMMPS and the -code would not be as general-purpose as it is without their expertise -and efforts. - -Axel Kohlmeyer (Temple U), akohlmey at gmail.com, SVN and Git repositories, indefatigable mail list responder, USER-CGSDK, USER-OMP, USER-COLVARS, USER-MOLFILE, USER-QMMM, USER-TALLY, and COMPRESS packages -Roy Pollock (LLNL), Ewald and PPPM solvers -Mike Brown (ORNL), brownw at ornl.gov, GPU and USER-INTEL package -Greg Wagner (Sandia), gjwagne at sandia.gov, MEAM package for MEAM potential (superseded by USER-MEAMC) -Mike Parks (Sandia), mlparks at sandia.gov, PERI package for Peridynamics -Rudra Mukherjee (JPL), Rudranarayan.M.Mukherjee at jpl.nasa.gov, POEMS package for articulated rigid body motion -Reese Jones (Sandia) and collaborators, rjones at sandia.gov, USER-ATC package for atom/continuum coupling -Ilya Valuev (JIHT), valuev at physik.hu-berlin.de, USER-AWPMD package for wave-packet MD -Christian Trott (U Tech Ilmenau), christian.trott at tu-ilmenau.de, USER-CUDA (obsoleted by KOKKOS) and KOKKOS packages -Andres Jaramillo-Botero (Caltech), ajaramil at wag.caltech.edu, USER-EFF package for electron force field -Christoph Kloss (JKU), Christoph.Kloss at jku.at, LIGGGHTS fork for granular models and granular/fluid coupling -Metin Aktulga (LBL), hmaktulga at lbl.gov, USER-REAXC package for C version of ReaxFF -Georg Gunzenmuller (EMI), georg.ganzenmueller at emi.fhg.de, USER-SMD and USER-SPH packages -Colin Denniston (U Western Ontario), cdennist at uwo.ca, USER-LB package :ul - -As discussed in "Section 13"_Section_history.html, LAMMPS -originated as a cooperative project between DOE labs and industrial -partners. Folks involved in the design and testing of the original -version of LAMMPS were the following: - -John Carpenter (Mayo Clinic, formerly at Cray Research) -Terry Stouch (Lexicon Pharmaceuticals, formerly at Bristol Myers Squibb) -Steve Lustig (Dupont) -Jim Belak (LLNL) :ul diff --git a/doc/src/Section_start.txt b/doc/src/Section_start.txt index cd445b3e14..4176432328 100644 --- a/doc/src/Section_start.txt +++ b/doc/src/Section_start.txt @@ -1,4 +1,4 @@ -"Previous Section"_Section_intro.html - "LAMMPS WWW Site"_lws - +"Previous Section"_Intro.html - "LAMMPS WWW Site"_lws - "LAMMPS Documentation"_ld - "LAMMPS Commands"_lc - "Next Section"_Section_commands.html :c @@ -934,9 +934,9 @@ Makefile.opt :ul LAMMPS can be built as either a static or shared library, which can then be called from another application or a scripting language. See -"this section"_Section_howto.html#howto_10 for more info on coupling -LAMMPS to other codes. See the "Python"_Python.html doc page for more -info on wrapping and running LAMMPS from Python. +the "Howto couple"_Howto_couple.html doc page for more info on +coupling LAMMPS to other codes. See the "Python"_Python.html doc page +for more info on wrapping and running LAMMPS from Python. Static library :h4 @@ -1039,16 +1039,16 @@ src/library.cpp and src/library.h. See the sample codes in examples/COUPLE/simple for examples of C++ and C and Fortran codes that invoke LAMMPS thru its library interface. -There are other examples as well in the COUPLE directory which are -discussed in "Section 6.10"_Section_howto.html#howto_10 of the manual. -See the "Python"_Python.html doc page for a description of the Python -wrapper provided with LAMMPS that operates through the LAMMPS library -interface. +There are other examples as well in the COUPLE directory which use +coupling ideas discussed on the "Howto couple"_Howto_couple.html doc +page. See the "Python"_Python.html doc page for a description of the +Python wrapper provided with LAMMPS that operates through the LAMMPS +library interface. The files src/library.cpp and library.h define the C-style API for -using LAMMPS as a library. See "Section -6.19"_Section_howto.html#howto_19 of the manual for a description of the -interface and how to extend it for your needs. +using LAMMPS as a library. See the "Howto library"_Howto_library.html +doc page for a description of the interface and how to extend it for +your needs. :line @@ -1391,16 +1391,16 @@ processors in all partitions must equal P. Thus the command "-partition 8x2 4 5" has 10 partitions and runs on a total of 25 processors. -Running with multiple partitions can e useful for running -"multi-replica simulations"_Section_howto.html#howto_5, where each -replica runs on on one or a few processors. Note that with MPI -installed on a machine (e.g. your desktop), you can run on more -(virtual) processors than you have physical processors. +Running with multiple partitions can be useful for running +"multi-replica simulations"_Howto_replica.html, where each replica +runs on on one or a few processors. Note that with MPI installed on a +machine (e.g. your desktop), you can run on more (virtual) processors +than you have physical processors. To run multiple independent simulations from one input script, using -multiple partitions, see "Section 6.4"_Section_howto.html#howto_4 -of the manual. World- and universe-style "variables"_variable.html -are useful in this context. +multiple partitions, see the "Howto multiple"_Howto_multiple.html doc +page. World- and universe-style "variables"_variable.html are useful +in this context. -plog file :pre @@ -1787,11 +1787,13 @@ communication, roughly 75% in the example above. The current C++ began with a complete rewrite of LAMMPS 2001, which was written in F90. Features of earlier versions of LAMMPS are listed -in "Section 13"_Section_history.html. The F90 and F77 versions -(2001 and 99) are also freely distributed as open-source codes; check -the "LAMMPS WWW Site"_lws for distribution information if you prefer -those versions. The 99 and 2001 versions are no longer under active -development; they do not have all the features of C++ LAMMPS. +on the "History page"_http://lammps.sandia.gov/history.html of the +LAMMPS website. The F90 and F77 versions (2001 and 99) are also +freely distributed as open-source codes; check the "History +page"_http://lammps.sandia.gov/history.html of the LAMMPS website for +info about those versions. The 99 and 2001 versions are no longer +under active development; they do not have all the features of C++ +LAMMPS. If you are a previous user of LAMMPS 2001, these are the most significant changes you will notice in C++ LAMMPS: diff --git a/doc/src/Speed.txt b/doc/src/Speed.txt index 1e2097ab1d..6c53d6bcf0 100644 --- a/doc/src/Speed.txt +++ b/doc/src/Speed.txt @@ -1,6 +1,6 @@ "Previous Section"_Package.html - "LAMMPS WWW Site"_lws - "LAMMPS Documentation"_ld - "LAMMPS Commands"_lc - "Next -Section"_Section_howto.html :c +Section"_Howto.html :c :link(lws,http://lammps.sandia.gov) :link(ld,Manual.html) diff --git a/doc/src/Tools.txt b/doc/src/Tools.txt index 4c5fbbd453..10e7f74a3d 100644 --- a/doc/src/Tools.txt +++ b/doc/src/Tools.txt @@ -1,4 +1,4 @@ -"Previous Section"_Section_perf.html - "LAMMPS WWW Site"_lws - "LAMMPS +"Previous Section"_Examples.html - "LAMMPS WWW Site"_lws - "LAMMPS Documentation"_ld - "LAMMPS Commands"_lc - "Next Section"_Modify.html :c @@ -142,8 +142,8 @@ The syntax for running the tool is chain < def.chain > data.file :pre See the def.chain or def.chain.ab files in the tools directory for -examples of definition files. This tool was used to create the -system for the "chain benchmark"_Section_perf.html. +examples of definition files. This tool was used to create the system +for the "chain benchmark"_Speed_bench.html. :line diff --git a/doc/src/angle_cosine_periodic.txt b/doc/src/angle_cosine_periodic.txt index 4bedae3246..108b081533 100644 --- a/doc/src/angle_cosine_periodic.txt +++ b/doc/src/angle_cosine_periodic.txt @@ -21,10 +21,10 @@ angle_coeff * 75.0 1 6 :pre [Description:] The {cosine/periodic} angle style uses the following potential, which -is commonly used in the "DREIDING"_Section_howto.html#howto_4 force -field, particularly for organometallic systems where {n} = 4 might be -used for an octahedral complex and {n} = 3 might be used for a -trigonal center: +is commonly used in the "DREIDING"_Howto_bioFF.html force field, +particularly for organometallic systems where {n} = 4 might be used +for an octahedral complex and {n} = 3 might be used for a trigonal +center: :c,image(Eqs/angle_cosine_periodic.jpg) diff --git a/doc/src/atom_style.txt b/doc/src/atom_style.txt index 0e6aa8a033..063f9e446c 100644 --- a/doc/src/atom_style.txt +++ b/doc/src/atom_style.txt @@ -20,7 +20,7 @@ style = {angle} or {atomic} or {body} or {bond} or {charge} or {dipole} or \ {body} args = bstyle bstyle-args bstyle = style of body particles bstyle-args = additional arguments specific to the bstyle - see the "body"_body.html doc page for details + see the "Howto body"_Howto_body.html doc page for details {tdpd} arg = Nspecies Nspecies = # of chemical species {template} arg = template-ID @@ -106,9 +106,9 @@ output the custom values. All of the above styles define point particles, except the {sphere}, {ellipsoid}, {electron}, {peri}, {wavepacket}, {line}, {tri}, and -{body} styles, which define finite-size particles. See "Section -6.14"_Section_howto.html#howto_14 for an overview of using finite-size -particle models with LAMMPS. +{body} styles, which define finite-size particles. See the "Howto +spherical"_Howto_spherical.html doc page for an overview of using +finite-size particle models with LAMMPS. All of the point-particle styles assign mass to particles on a per-type basis, using the "mass"_mass.html command, The finite-size @@ -224,15 +224,16 @@ the {bstyle} argument. Body particles can represent complex entities, such as surface meshes of discrete points, collections of sub-particles, deformable objects, etc. -The "body"_body.html doc page describes the body styles LAMMPS -currently supports, and provides more details as to the kind of body -particles they represent. For all styles, each body particle stores -moments of inertia and a quaternion 4-vector, so that its orientation -and position can be time integrated due to forces and torques. +The "Howto body"_Howto_body.html doc page describes the body styles +LAMMPS currently supports, and provides more details as to the kind of +body particles they represent. For all styles, each body particle +stores moments of inertia and a quaternion 4-vector, so that its +orientation and position can be time integrated due to forces and +torques. Note that there may be additional arguments required along with the {bstyle} specification, in the atom_style body command. These -arguments are described in the "body"_body.html doc page. +arguments are described on the "Howto body"_Howto_body.html doc page. :line diff --git a/doc/src/body.txt b/doc/src/body.txt index 4a39ac25d8..83b725d8cc 100644 --- a/doc/src/body.txt +++ b/doc/src/body.txt @@ -17,8 +17,8 @@ surface meshes of discrete points, collections of sub-particles, deformable objects, etc. Note that other kinds of finite-size spherical and aspherical particles are also supported by LAMMPS, such as spheres, ellipsoids, line segments, and triangles, but they are -simpler entities that body particles. See "Section -6.14"_Section_howto.html#howto_14 for a general overview of all +simpler entities that body particles. See the "Howto +body"_Howto_.html doc page for a general overview of all these particle types. Body particles are used via the "atom_style body"_atom_style.html diff --git a/doc/src/boundary.txt b/doc/src/boundary.txt index ce638f11b3..7ee897ffa4 100644 --- a/doc/src/boundary.txt +++ b/doc/src/boundary.txt @@ -82,9 +82,9 @@ and xhi faces of the box are planes tilting in the +y direction as y increases. These tilted planes are shrink-wrapped around the atoms to determine the x extent of the box. -See "Section 6.12"_Section_howto.html#howto_12 of the doc pages -for a geometric description of triclinic boxes, as defined by LAMMPS, -and how to transform these parameters to and from other commonly used +See the "Howto triclinic"_Howto_triclinic.html doc page for a +geometric description of triclinic boxes, as defined by LAMMPS, and +how to transform these parameters to and from other commonly used triclinic representations. [Restrictions:] diff --git a/doc/src/box.txt b/doc/src/box.txt index a6207ae993..6dc093ad81 100644 --- a/doc/src/box.txt +++ b/doc/src/box.txt @@ -30,9 +30,9 @@ For triclinic (non-orthogonal) simulation boxes, the {tilt} keyword allows simulation domains to be created with arbitrary tilt factors, e.g. via the "create_box"_create_box.html or "read_data"_read_data.html commands. Tilt factors determine how -skewed the triclinic box is; see "this -section"_Section_howto.html#howto_12 of the manual for a discussion of -triclinic boxes in LAMMPS. +skewed the triclinic box is; see the "Howto +triclinic"_Howto_triclinic.html doc page for a discussion of triclinic +boxes in LAMMPS. LAMMPS normally requires that no tilt factor can skew the box more than half the distance of the parallel box length, which is the 1st diff --git a/doc/src/change_box.txt b/doc/src/change_box.txt index 2c7a890d4c..8f3fda263f 100644 --- a/doc/src/change_box.txt +++ b/doc/src/change_box.txt @@ -75,9 +75,9 @@ The "create_box"_create_box.html, "read data"_read_data.html, and simulation box is orthogonal or triclinic and their doc pages explain the meaning of the xy,xz,yz tilt factors. -See "Section 6.12"_Section_howto.html#howto_12 of the doc pages -for a geometric description of triclinic boxes, as defined by LAMMPS, -and how to transform these parameters to and from other commonly used +See the "Howto triclinic"_Howto_triclinic.html doc page for a +geometric description of triclinic boxes, as defined by LAMMPS, and +how to transform these parameters to and from other commonly used triclinic representations. The keywords used in this command are applied sequentially to the @@ -140,8 +140,8 @@ transformation in the sequence. If skew is exceeded before the final transformation this can be avoided by changing the order of the sequence, or breaking the transformation into two or more smaller transformations. For more information on the allowed limits for box -skew see the discussion on triclinic boxes on "this -page"_Section_howto.html#howto_12. +skew see the discussion on triclinic boxes on "Howto +triclinic"_Howto_triclinic.html doc page. :line @@ -258,9 +258,7 @@ command. :line The {ortho} and {triclinic} keywords convert the simulation box to be -orthogonal or triclinic (non-orthogonal). See "this -section"_Section_howto#howto_13 for a discussion of how non-orthogonal -boxes are represented in LAMMPS. +orthogonal or triclinic (non-orthogonal). The simulation box is defined as either orthogonal or triclinic when it is created via the "create_box"_create_box.html, @@ -271,8 +269,8 @@ These keywords allow you to toggle the existing simulation box from orthogonal to triclinic and vice versa. For example, an initial equilibration simulation can be run in an orthogonal box, the box can be toggled to triclinic, and then a "non-equilibrium MD (NEMD) -simulation"_Section_howto.html#howto_13 can be run with deformation -via the "fix deform"_fix_deform.html command. +simulation"_Howto_nemd.html can be run with deformation via the "fix +deform"_fix_deform.html command. If the simulation box is currently triclinic and has non-zero tilt in xy, yz, or xz, then it cannot be converted to an orthogonal box. diff --git a/doc/src/compute.txt b/doc/src/compute.txt index 532a5414e3..105571b82a 100644 --- a/doc/src/compute.txt +++ b/doc/src/compute.txt @@ -33,7 +33,7 @@ information about a previous state of the system. Defining a compute does not perform a computation. Instead computes are invoked by other LAMMPS commands as needed, e.g. to calculate a temperature needed for a thermostat fix or to generate thermodynamic or dump file output. -See this "howto section"_Section_howto.html#howto_15 for a summary of +See the "Howto output"_Howto_output.html doc page for a summary of various LAMMPS output options, many of which involve computes. The ID of a compute can only contain alphanumeric characters and diff --git a/doc/src/compute_ackland_atom.txt b/doc/src/compute_ackland_atom.txt index 3fd838d957..e75ad534eb 100644 --- a/doc/src/compute_ackland_atom.txt +++ b/doc/src/compute_ackland_atom.txt @@ -60,7 +60,7 @@ which computes this quantity.- This compute calculates a per-atom vector, which can be accessed by any command that uses per-atom values from a compute as input. See -"Section 6.15"_Section_howto.html#howto_15 for an overview of +the "Howto output"_Howto_output.html doc page for an overview of LAMMPS output options. [Restrictions:] diff --git a/doc/src/compute_angle.txt b/doc/src/compute_angle.txt index 2c363ce8f6..1deb3a4b1b 100644 --- a/doc/src/compute_angle.txt +++ b/doc/src/compute_angle.txt @@ -37,8 +37,8 @@ This compute calculates a global vector of length N where N is the number of sub_styles defined by the "angle_style hybrid"_angle_style.html command, which can be accessed by indices 1-N. These values can be used by any command that uses global scalar -or vector values from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output +or vector values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. The vector values are "extensive" and will be in energy diff --git a/doc/src/compute_angle_local.txt b/doc/src/compute_angle_local.txt index 0ee1d32d7d..487b41eaf3 100644 --- a/doc/src/compute_angle_local.txt +++ b/doc/src/compute_angle_local.txt @@ -70,8 +70,8 @@ array is the number of angles. If a single keyword is specified, a local vector is produced. If two or more keywords are specified, a local array is produced where the number of columns = the number of keywords. The vector or array can be accessed by any command that -uses local values from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output +uses local values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. The output for {theta} will be in degrees. The output for {eng} will diff --git a/doc/src/compute_angmom_chunk.txt b/doc/src/compute_angmom_chunk.txt index 813da15eea..c97af96f49 100644 --- a/doc/src/compute_angmom_chunk.txt +++ b/doc/src/compute_angmom_chunk.txt @@ -30,10 +30,9 @@ chunk/atom"_compute_chunk_atom.html command, which assigns each atom to a single chunk (or no chunk). The ID for this command is specified as chunkID. For example, a single chunk could be the atoms in a molecule or atoms in a spatial bin. See the "compute -chunk/atom"_compute_chunk_atom.html doc page and "Section -6.23"_Section_howto.html#howto_23 for details of how chunks can be -defined and examples of how they can be used to measure properties of -a system. +chunk/atom"_compute_chunk_atom.html and "Howto chunk"_Howto_chunk.html +doc pages for details of how chunks can be defined and examples of how +they can be used to measure properties of a system. This compute calculates the 3 components of the angular momentum vector for each chunk, due to the velocity/momentum of the individual @@ -73,8 +72,8 @@ number of chunks {Nchunk} as calculated by the specified "compute chunk/atom"_compute_chunk_atom.html command. The number of columns = 3 for the 3 xyz components of the angular momentum for each chunk. These values can be accessed by any command that uses global array -values from a compute as input. See "Section -6.15"_Section_howto.html#howto_15 for an overview of LAMMPS output +values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. The array values are "intensive". The array values will be in diff --git a/doc/src/compute_basal_atom.txt b/doc/src/compute_basal_atom.txt index b59a3fd4c8..e0ac6b0a60 100644 --- a/doc/src/compute_basal_atom.txt +++ b/doc/src/compute_basal_atom.txt @@ -46,9 +46,8 @@ in examples/USER/misc/basal. This compute calculates a per-atom array with 3 columns, which can be accessed by indices 1-3 by any command that uses per-atom values from -a compute as input. See "Section -6.15"_Section_howto.html#howto_15 for an overview of LAMMPS output -options. +a compute as input. See the "Howto output"_Howto_output.html doc page +for an overview of LAMMPS output options. The per-atom vector values are unitless since the 3 columns represent components of a unit vector. diff --git a/doc/src/compute_body_local.txt b/doc/src/compute_body_local.txt index 12ce218853..f387e61c78 100644 --- a/doc/src/compute_body_local.txt +++ b/doc/src/compute_body_local.txt @@ -32,9 +32,8 @@ Define a computation that calculates properties of individual body sub-particles. The number of datums generated, aggregated across all processors, equals the number of body sub-particles plus the number of non-body particles in the system, modified by the group parameter as -explained below. See "Section 6.14"_Section_howto.html#howto_14 -of the manual and the "body"_body.html doc page for more details on -using body particles. +explained below. See the "Howto body"_Howto_body.html doc page for +more details on using body particles. The local data stored by this command is generated by looping over all the atoms. An atom will only be included if it is in the group. If @@ -58,8 +57,8 @@ group. For a body particle, the {integer} keywords refer to fields calculated by the body style for each sub-particle. The body style, as specified by the "atom_style body"_atom_style.html, determines how many fields -exist and what they are. See the "body"_body.html doc page for -details of the different styles. +exist and what they are. See the "Howto_body"_Howto_body.html doc +page for details of the different styles. Here is an example of how to output body information using the "dump local"_dump.html command with this compute. If fields 1,2,3 for the @@ -78,9 +77,9 @@ array is the number of datums as described above. If a single keyword is specified, a local vector is produced. If two or more keywords are specified, a local array is produced where the number of columns = the number of keywords. The vector or array can be accessed by any -command that uses local values from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output -options. +command that uses local values from a compute as input. See the +"Howto output"_Howto_output.html doc page for an overview of LAMMPS +output options. The "units"_units.html for output values depend on the body style. diff --git a/doc/src/compute_bond.txt b/doc/src/compute_bond.txt index 6c4384b080..ac0e50872b 100644 --- a/doc/src/compute_bond.txt +++ b/doc/src/compute_bond.txt @@ -37,8 +37,8 @@ This compute calculates a global vector of length N where N is the number of sub_styles defined by the "bond_style hybrid"_bond_style.html command, which can be accessed by indices 1-N. These values can be used by any command that uses global scalar or -vector values from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output +vector values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. The vector values are "extensive" and will be in energy diff --git a/doc/src/compute_bond_local.txt b/doc/src/compute_bond_local.txt index 58d96f9ee4..868b43caa9 100644 --- a/doc/src/compute_bond_local.txt +++ b/doc/src/compute_bond_local.txt @@ -116,8 +116,8 @@ array is the number of bonds. If a single keyword is specified, a local vector is produced. If two or more keywords are specified, a local array is produced where the number of columns = the number of keywords. The vector or array can be accessed by any command that -uses local values from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output +uses local values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. The output for {dist} will be in distance "units"_units.html. The diff --git a/doc/src/compute_centro_atom.txt b/doc/src/compute_centro_atom.txt index 4e4b03d167..bace0d8739 100644 --- a/doc/src/compute_centro_atom.txt +++ b/doc/src/compute_centro_atom.txt @@ -97,8 +97,8 @@ too frequently or to have multiple compute/dump commands, each with a By default, this compute calculates the centrosymmetry value for each atom as a per-atom vector, which can be accessed by any command that -uses per-atom values from a compute as input. See "Section -6.15"_Section_howto.html#howto_15 for an overview of LAMMPS output +uses per-atom values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. If the {axes} keyword setting is {yes}, then a per-atom array is diff --git a/doc/src/compute_chunk_atom.txt b/doc/src/compute_chunk_atom.txt index 00a75f50c4..fc0de28b6a 100644 --- a/doc/src/compute_chunk_atom.txt +++ b/doc/src/compute_chunk_atom.txt @@ -101,14 +101,13 @@ msd/chunk"_compute_msd_chunk.html. Or they can be used by the "fix ave/chunk"_fix_ave_chunk.html command to sum and time average a variety of per-atom properties over the atoms in each chunk. Or they can simply be accessed by any command that uses per-atom values from a -compute as input, as discussed in "Section -6.15"_Section_howto.html#howto_15. +compute as input, as discussed on the "Howto output"_Howto_output.html +doc page. -See "Section 6.23"_Section_howto.html#howto_23 for an overview of -how this compute can be used with a variety of other commands to -tabulate properties of a simulation. The howto section gives several -examples of input script commands that can be used to calculate -interesting properties. +See the "Howto chunk"_Howto_chunk.html doc page for an overview of how +this compute can be used with a variety of other commands to tabulate +properties of a simulation. The page gives several examples of input +script commands that can be used to calculate interesting properties. Conceptually it is important to realize that this compute does two simple things. First, it sets the value of {Nchunk} = the number of @@ -167,11 +166,11 @@ or the bounds specified by the optional {bounds} keyword. For orthogonal simulation boxes, the bins are layers, pencils, or boxes aligned with the xyz coordinate axes. For triclinic (non-orthogonal) simulation boxes, the bin faces are parallel to the -tilted faces of the simulation box. See "this -section"_Section_howto.html#howto_12 of the manual for a discussion of -the geometry of triclinic boxes in LAMMPS. As described there, a -tilted simulation box has edge vectors a,b,c. In that nomenclature, -bins in the x dimension have faces with normals in the "b" cross "c" +tilted faces of the simulation box. See the "Howto +triclinic"_Howto_triclinic.html doc page for a discussion of the +geometry of triclinic boxes in LAMMPS. As described there, a tilted +simulation box has edge vectors a,b,c. In that nomenclature, bins in +the x dimension have faces with normals in the "b" cross "c" direction. Bins in y have faces normal to the "a" cross "c" direction. And bins in z have faces normal to the "a" cross "b" direction. Note that in order to define the size and position of @@ -626,7 +625,7 @@ cylinder, x for a y-axis cylinder, and x for a z-axis cylinder. This compute calculates a per-atom vector, which can be accessed by any command that uses per-atom values from a compute as input. See -"Section 6.15"_Section_howto.html#howto_15 for an overview of +the "Howto output"_Howto_output.html doc page for an overview of LAMMPS output options. The per-atom vector values are unitless chunk IDs, ranging from 1 to diff --git a/doc/src/compute_cluster_atom.txt b/doc/src/compute_cluster_atom.txt index 94113de5f2..12ecb8f173 100644 --- a/doc/src/compute_cluster_atom.txt +++ b/doc/src/compute_cluster_atom.txt @@ -84,7 +84,7 @@ the neighbor list. This compute calculates a per-atom vector, which can be accessed by any command that uses per-atom values from a compute as input. See -"Section 6.15"_Section_howto.html#howto_15 for an overview of +the "Howto output"_Howto_output.html doc page for an overview of LAMMPS output options. The per-atom vector values will be an ID > 0, as explained above. diff --git a/doc/src/compute_cna_atom.txt b/doc/src/compute_cna_atom.txt index 23289b0132..9c4814560d 100644 --- a/doc/src/compute_cna_atom.txt +++ b/doc/src/compute_cna_atom.txt @@ -74,7 +74,7 @@ too frequently or to have multiple compute/dump commands, each with a This compute calculates a per-atom vector, which can be accessed by any command that uses per-atom values from a compute as input. See -"Section 6.15"_Section_howto.html#howto_15 for an overview of +the "Howto output"_Howto_output.html doc page for an overview of LAMMPS output options. The per-atom vector values will be a number from 0 to 5, as explained diff --git a/doc/src/compute_cnp_atom.txt b/doc/src/compute_cnp_atom.txt index 16a51f5241..aca7e351ec 100644 --- a/doc/src/compute_cnp_atom.txt +++ b/doc/src/compute_cnp_atom.txt @@ -78,7 +78,7 @@ too frequently or to have multiple compute/dump commands, each with a This compute calculates a per-atom vector, which can be accessed by any command that uses per-atom values from a compute as input. See -"Section 6.15"_Section_howto.html#howto_15 for an overview of +the "Howto output"_Howto_output.html doc page for an overview of LAMMPS output options. The per-atom vector values will be real positive numbers. Some typical CNP diff --git a/doc/src/compute_com.txt b/doc/src/compute_com.txt index b0e0c14e42..08bb08b142 100644 --- a/doc/src/compute_com.txt +++ b/doc/src/compute_com.txt @@ -41,9 +41,8 @@ image"_set.html command. This compute calculates a global vector of length 3, which can be accessed by indices 1-3 by any command that uses global vector values -from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output -options. +from a compute as input. See the "Howto output"_Howto_output.html doc +page for an overview of LAMMPS output options. The vector values are "intensive". The vector values will be in distance "units"_units.html. diff --git a/doc/src/compute_com_chunk.txt b/doc/src/compute_com_chunk.txt index d497585cb0..f28355d6c5 100644 --- a/doc/src/compute_com_chunk.txt +++ b/doc/src/compute_com_chunk.txt @@ -30,10 +30,9 @@ chunk/atom"_compute_chunk_atom.html command, which assigns each atom to a single chunk (or no chunk). The ID for this command is specified as chunkID. For example, a single chunk could be the atoms in a molecule or atoms in a spatial bin. See the "compute -chunk/atom"_compute_chunk_atom.html doc page and "Section -6.23"_Section_howto.html#howto_23 for details of how chunks can be -defined and examples of how they can be used to measure properties of -a system. +chunk/atom"_compute_chunk_atom.html and "Howto chunk"_Howto_chunk.html +doc pages for details of how chunks can be defined and examples of how +they can be used to measure properties of a system. This compute calculates the x,y,z coordinates of the center-of-mass for each chunk, which includes all effects due to atoms passing thru @@ -71,9 +70,8 @@ number of chunks {Nchunk} as calculated by the specified "compute chunk/atom"_compute_chunk_atom.html command. The number of columns = 3 for the x,y,z center-of-mass coordinates of each chunk. These values can be accessed by any command that uses global array values -from a compute as input. See "Section -6.15"_Section_howto.html#howto_15 for an overview of LAMMPS output -options. +from a compute as input. See the "Howto output"_Howto_output.html doc +page for an overview of LAMMPS output options. The array values are "intensive". The array values will be in distance "units"_units.html. diff --git a/doc/src/compute_contact_atom.txt b/doc/src/compute_contact_atom.txt index f0bd62f4e8..ea4158e3b1 100644 --- a/doc/src/compute_contact_atom.txt +++ b/doc/src/compute_contact_atom.txt @@ -36,7 +36,7 @@ specified compute group. This compute calculates a per-atom vector, whose values can be accessed by any command that uses per-atom values from a compute as -input. See "Section 6.15"_Section_howto.html#howto_15 for an +input. See the "Howto output"_Howto_output.html doc page for an overview of LAMMPS output options. The per-atom vector values will be a number >= 0.0, as explained diff --git a/doc/src/compute_coord_atom.txt b/doc/src/compute_coord_atom.txt index a88f7ec729..06b565aedc 100644 --- a/doc/src/compute_coord_atom.txt +++ b/doc/src/compute_coord_atom.txt @@ -109,9 +109,8 @@ array, with N columns. For {cstyle} orientorder, this compute calculates a per-atom vector. These values can be accessed by any command that uses per-atom values -from a compute as input. See "Section -6.15"_Section_howto.html#howto_15 for an overview of LAMMPS output -options. +from a compute as input. See the "Howto output"_Howto_output.html doc +page for an overview of LAMMPS output options. The per-atom vector or array values will be a number >= 0.0, as explained above. diff --git a/doc/src/compute_damage_atom.txt b/doc/src/compute_damage_atom.txt index 918fbf65ef..e262ee0b1f 100644 --- a/doc/src/compute_damage_atom.txt +++ b/doc/src/compute_damage_atom.txt @@ -44,7 +44,7 @@ group. This compute calculates a per-atom vector, which can be accessed by any command that uses per-atom values from a compute as input. See -"Section 6.15"_Section_howto.html#howto_15 for an overview of +the "Howto output"_Howto_output.html doc page for an overview of LAMMPS output options. The per-atom vector values are unitless numbers (damage) >= 0.0. diff --git a/doc/src/compute_dihedral.txt b/doc/src/compute_dihedral.txt index a3c3dff8d6..67c97b60f1 100644 --- a/doc/src/compute_dihedral.txt +++ b/doc/src/compute_dihedral.txt @@ -37,8 +37,8 @@ This compute calculates a global vector of length N where N is the number of sub_styles defined by the "dihedral_style hybrid"_dihedral_style.html command. which can be accessed by indices 1-N. These values can be used by any command that uses global scalar -or vector values from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output +or vector values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. The vector values are "extensive" and will be in energy diff --git a/doc/src/compute_dihedral_local.txt b/doc/src/compute_dihedral_local.txt index 865e86fddb..d2051a51bd 100644 --- a/doc/src/compute_dihedral_local.txt +++ b/doc/src/compute_dihedral_local.txt @@ -62,8 +62,8 @@ array is the number of dihedrals. If a single keyword is specified, a local vector is produced. If two or more keywords are specified, a local array is produced where the number of columns = the number of keywords. The vector or array can be accessed by any command that -uses local values from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output +uses local values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. The output for {phi} will be in degrees. diff --git a/doc/src/compute_dilatation_atom.txt b/doc/src/compute_dilatation_atom.txt index ce00f7f12a..161e73c7ff 100644 --- a/doc/src/compute_dilatation_atom.txt +++ b/doc/src/compute_dilatation_atom.txt @@ -47,8 +47,9 @@ compute group. [Output info:] This compute calculates a per-atom vector, which can be accessed by -any command that uses per-atom values from a compute as input. See -Section_howto 15 for an overview of LAMMPS output options. +any command that uses per-atom values from a compute as input. See +the "Howto output"_Howto_output.html doc page for an overview of +LAMMPS output options. The per-atom vector values are unitless numbers (theta) >= 0.0. diff --git a/doc/src/compute_dipole_chunk.txt b/doc/src/compute_dipole_chunk.txt index 75131ffbb1..5f8d6689c4 100644 --- a/doc/src/compute_dipole_chunk.txt +++ b/doc/src/compute_dipole_chunk.txt @@ -32,10 +32,9 @@ chunk/atom"_compute_chunk_atom.html command, which assigns each atom to a single chunk (or no chunk). The ID for this command is specified as chunkID. For example, a single chunk could be the atoms in a molecule or atoms in a spatial bin. See the "compute -chunk/atom"_compute_chunk_atom.html doc page and "Section -6.23"_Section_howto.html#howto_23 for details of how chunks can be -defined and examples of how they can be used to measure properties of -a system. +chunk/atom"_compute_chunk_atom.html and "Howto chunk"_Howto_chunk.html +doc pages for details of how chunks can be defined and examples of how +they can be used to measure properties of a system. This compute calculates the x,y,z coordinates of the dipole vector and the total dipole moment for each chunk, which includes all effects @@ -76,8 +75,8 @@ number of chunks {Nchunk} as calculated by the specified "compute chunk/atom"_compute_chunk_atom.html command. The number of columns = 4 for the x,y,z dipole vector components and the total dipole of each chunk. These values can be accessed by any command that uses global -array values from a compute as input. See "Section -6.15"_Section_howto.html#howto_15 for an overview of LAMMPS output +array values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. The array values are "intensive". The array values will be in diff --git a/doc/src/compute_displace_atom.txt b/doc/src/compute_displace_atom.txt index 00e5f696c1..5636cc02f0 100644 --- a/doc/src/compute_displace_atom.txt +++ b/doc/src/compute_displace_atom.txt @@ -118,9 +118,8 @@ would be empty. This compute calculates a per-atom array with 4 columns, which can be accessed by indices 1-4 by any command that uses per-atom values from -a compute as input. See "Section -6.15"_Section_howto.html#howto_15 for an overview of LAMMPS output -options. +a compute as input. See the "Howto output"_Howto_output.html doc page +for an overview of LAMMPS output options. The per-atom array values will be in distance "units"_units.html. diff --git a/doc/src/compute_dpd.txt b/doc/src/compute_dpd.txt index 0e43feb9d2..a5620d34b3 100644 --- a/doc/src/compute_dpd.txt +++ b/doc/src/compute_dpd.txt @@ -40,9 +40,9 @@ where N is the number of particles in the system [Output info:] This compute calculates a global vector of length 5 (U_cond, U_mech, -U_chem, dpdTheta, N_particles), which can be accessed by indices 1-5. See -"this section"_Section_howto.html#howto_15 for an overview of LAMMPS -output options. +U_chem, dpdTheta, N_particles), which can be accessed by indices 1-5. +See the "Howto output"_Howto_output.html doc page for an overview of +LAMMPS output options. The vector values will be in energy and temperature "units"_units.html. diff --git a/doc/src/compute_dpd_atom.txt b/doc/src/compute_dpd_atom.txt index 0532fc60c6..ed0fd2410b 100644 --- a/doc/src/compute_dpd_atom.txt +++ b/doc/src/compute_dpd_atom.txt @@ -34,9 +34,9 @@ particles. [Output info:] This compute calculates a per-particle array with 4 columns (u_cond, -u_mech, u_chem, dpdTheta), which can be accessed by indices 1-4 by any command -that uses per-particle values from a compute as input. See -"Section 6.15"_Section_howto.html#howto_15 for an overview of +u_mech, u_chem, dpdTheta), which can be accessed by indices 1-4 by any +command that uses per-particle values from a compute as input. See +the "Howto output"_Howto_output.html doc page for an overview of LAMMPS output options. The per-particle array values will be in energy (u_cond, u_mech, u_chem) diff --git a/doc/src/compute_edpd_temp_atom.txt b/doc/src/compute_edpd_temp_atom.txt index 5b8c8ebd67..9011c3c823 100644 --- a/doc/src/compute_edpd_temp_atom.txt +++ b/doc/src/compute_edpd_temp_atom.txt @@ -32,9 +32,9 @@ For more details please see "(Espanol1997)"_#Espanol1997 and [Output info:] This compute calculates a per-atom vector, which can be accessed by -any command that uses per-atom values from a compute as input. See -"Section 6.15"_Section_howto.html#howto_15 for an overview of -LAMMPS output options. +any command that uses per-atom values from a compute as input. See the +"Howto output"_Howto_output.html doc page for an overview of LAMMPS +output options. The per-atom vector values will be in temperature "units"_units.html. diff --git a/doc/src/compute_entropy_atom.txt b/doc/src/compute_entropy_atom.txt index f7e7b8a667..7fdc1f4af2 100644 --- a/doc/src/compute_entropy_atom.txt +++ b/doc/src/compute_entropy_atom.txt @@ -98,8 +98,8 @@ compute 1 all entropy/atom 0.25 7.3 avg yes 5.1 :pre By default, this compute calculates the pair entropy value for each atom as a per-atom vector, which can be accessed by any command that -uses per-atom values from a compute as input. See "Section -6.15"_Section_howto.html#howto_15 for an overview of LAMMPS output +uses per-atom values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. The pair entropy values have units of the Boltzmann constant. They are diff --git a/doc/src/compute_erotate_asphere.txt b/doc/src/compute_erotate_asphere.txt index b9a486c32e..24e6e5e6f7 100644 --- a/doc/src/compute_erotate_asphere.txt +++ b/doc/src/compute_erotate_asphere.txt @@ -40,7 +40,7 @@ will be the same as in 3d. This compute calculates a global scalar (the KE). This value can be used by any command that uses a global scalar value from a compute as -input. See "Section 6.15"_Section_howto.html#howto_15 for an +input. See the "Howto output"_Howto_output.html doc page for an overview of LAMMPS output options. The scalar value calculated by this compute is "extensive". The diff --git a/doc/src/compute_erotate_rigid.txt b/doc/src/compute_erotate_rigid.txt index dec0939a43..c8527d7073 100644 --- a/doc/src/compute_erotate_rigid.txt +++ b/doc/src/compute_erotate_rigid.txt @@ -41,9 +41,9 @@ calculation. This compute calculates a global scalar (the summed rotational energy of all the rigid bodies). This value can be used by any command that -uses a global scalar value from a compute as input. See -"Section 6.15"_Section_howto.html#howto_15 for an overview of -LAMMPS output options. +uses a global scalar value from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output +options. The scalar value calculated by this compute is "extensive". The scalar value will be in energy "units"_units.html. diff --git a/doc/src/compute_erotate_sphere.txt b/doc/src/compute_erotate_sphere.txt index 41e80b0154..8abc9a53ad 100644 --- a/doc/src/compute_erotate_sphere.txt +++ b/doc/src/compute_erotate_sphere.txt @@ -35,7 +35,7 @@ as in 3d. This compute calculates a global scalar (the KE). This value can be used by any command that uses a global scalar value from a compute as -input. See "Section 6.15"_Section_howto.html#howto_15 for an +input. See the "Howto output"_Howto_output.html doc page for an overview of LAMMPS output options. The scalar value calculated by this compute is "extensive". The diff --git a/doc/src/compute_erotate_sphere_atom.txt b/doc/src/compute_erotate_sphere_atom.txt index a0081ff6a8..0bea315a89 100644 --- a/doc/src/compute_erotate_sphere_atom.txt +++ b/doc/src/compute_erotate_sphere_atom.txt @@ -39,7 +39,7 @@ in the specified compute group or for point particles with a radius = This compute calculates a per-atom vector, which can be accessed by any command that uses per-atom values from a compute as input. See -"Section 6.15"_Section_howto.html#howto_15 for an overview of +the "Howto output"_Howto_output.html doc page for an overview of LAMMPS output options. The per-atom vector values will be in energy "units"_units.html. diff --git a/doc/src/compute_event_displace.txt b/doc/src/compute_event_displace.txt index 5e3a0c8599..17c4288911 100644 --- a/doc/src/compute_event_displace.txt +++ b/doc/src/compute_event_displace.txt @@ -43,7 +43,7 @@ local atom displacements and may generate "false positives." This compute calculates a global scalar (the flag). This value can be used by any command that uses a global scalar value from a compute as -input. See "Section 6.15"_Section_howto.html#howto_15 for an +input. See the "Howto output"_Howto_output.html doc page for an overview of LAMMPS output options. The scalar value calculated by this compute is "intensive". The diff --git a/doc/src/compute_fep.txt b/doc/src/compute_fep.txt index 9bbae7b20f..f0ce3fd704 100644 --- a/doc/src/compute_fep.txt +++ b/doc/src/compute_fep.txt @@ -219,8 +219,8 @@ unperturbed parameters. The energies include kspace terms if these are used in the simulation. These output results can be used by any command that uses a global -scalar or vector from a compute as input. See "Section -6.15"_Section_howto.html#howto_15 for an overview of LAMMPS output +scalar or vector from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. For example, the computed values can be averaged using "fix ave/time"_fix_ave_time.html. diff --git a/doc/src/compute_global_atom.txt b/doc/src/compute_global_atom.txt index 28b4aa2461..f40810b70c 100644 --- a/doc/src/compute_global_atom.txt +++ b/doc/src/compute_global_atom.txt @@ -67,7 +67,7 @@ this command. This command will then assign the global chunk value to each atom in the chunk, producing a per-atom vector or per-atom array as output. The per-atom values can then be output to a dump file or used by any command that uses per-atom values from a compute as input, -as discussed in "Section 6.15"_Section_howto.html#howto_15. +as discussed on the "Howto output"_Howto_output.html doc page. As a concrete example, these commands will calculate the displacement of each atom from the center-of-mass of the molecule it is in, and @@ -203,7 +203,7 @@ vector. If multiple inputs are specified, this compute produces a per-atom array values, where the number of columns is equal to the number of inputs specified. These values can be used by any command that uses per-atom vector or array values from a compute as input. -See "Section 6.15"_Section_howto.html#howto_15 for an overview of +See the "Howto output"_Howto_output.html doc page for an overview of LAMMPS output options. The per-atom vector or array values will be in whatever units the diff --git a/doc/src/compute_group_group.txt b/doc/src/compute_group_group.txt index f10547339d..8f992791d2 100644 --- a/doc/src/compute_group_group.txt +++ b/doc/src/compute_group_group.txt @@ -123,8 +123,8 @@ group-group calculations are performed. This compute calculates a global scalar (the energy) and a global vector of length 3 (force), which can be accessed by indices 1-3. These values can be used by any command that uses global scalar or -vector values from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output +vector values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. Both the scalar and vector values calculated by this compute are diff --git a/doc/src/compute_gyration.txt b/doc/src/compute_gyration.txt index dd71431527..3d698609ca 100644 --- a/doc/src/compute_gyration.txt +++ b/doc/src/compute_gyration.txt @@ -55,8 +55,8 @@ using the "set image"_set.html command. This compute calculates a global scalar (Rg) and a global vector of length 6 (Rg^2 tensor), which can be accessed by indices 1-6. These values can be used by any command that uses a global scalar value or -vector values from a compute as input. See "Section -6.15"_Section_howto.html#howto_15 for an overview of LAMMPS output +vector values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. The scalar and vector values calculated by this compute are diff --git a/doc/src/compute_gyration_chunk.txt b/doc/src/compute_gyration_chunk.txt index 3e338213cf..ef14a456f3 100644 --- a/doc/src/compute_gyration_chunk.txt +++ b/doc/src/compute_gyration_chunk.txt @@ -35,10 +35,9 @@ chunk/atom"_compute_chunk_atom.html command, which assigns each atom to a single chunk (or no chunk). The ID for this command is specified as chunkID. For example, a single chunk could be the atoms in a molecule or atoms in a spatial bin. See the "compute -chunk/atom"_compute_chunk_atom.html doc page and "Section -6.23"_Section_howto.html#howto_23 for details of how chunks can be -defined and examples of how they can be used to measure properties of -a system. +chunk/atom"_compute_chunk_atom.html and "Howto chunk"_Howto_chunk.html +doc pages for details of how chunks can be defined and examples of how +they can be used to measure properties of a system. This compute calculates the radius of gyration Rg for each chunk, which includes all effects due to atoms passing thru periodic @@ -93,8 +92,8 @@ calculated by the specified "compute chunk/atom"_compute_chunk_atom.html command. If the {tensor} keyword is specified, the global array has 6 columns. The vector or array can be accessed by any command that uses global values from a compute as -input. See "this section"_Section_howto.html#howto_15 for an overview -of LAMMPS output options. +input. See the "Howto output"_Howto_output.html doc page for an +overview of LAMMPS output options. All the vector or array values calculated by this compute are "intensive". The vector or array values will be in distance diff --git a/doc/src/compute_heat_flux.txt b/doc/src/compute_heat_flux.txt index 39a1470201..84c4951328 100644 --- a/doc/src/compute_heat_flux.txt +++ b/doc/src/compute_heat_flux.txt @@ -32,9 +32,9 @@ or to calculate a thermal conductivity using the equilibrium Green-Kubo formalism. For other non-equilibrium ways to compute a thermal conductivity, see -"this section"_Section_howto.html#howto_20. These include use of the -"fix thermal/conductivity"_fix_thermal_conductivity.html command for -the Muller-Plathe method. Or the "fix heat"_fix_heat.html command +the "Howto kappa"_Howto_kappa.html doc page.. These include use of +the "fix thermal/conductivity"_fix_thermal_conductivity.html command +for the Muller-Plathe method. Or the "fix heat"_fix_heat.html command which can add or subtract heat from groups of atoms. The compute takes three arguments which are IDs of other @@ -99,8 +99,8 @@ result should be: average conductivity ~0.29 in W/mK. This compute calculates a global vector of length 6 (total heat flux vector, followed by convective heat flux vector), which can be accessed by indices 1-6. These values can be used by any command that -uses global vector values from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output +uses global vector values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. The vector values calculated by this compute are "extensive", meaning diff --git a/doc/src/compute_hexorder_atom.txt b/doc/src/compute_hexorder_atom.txt index cdf47e0894..1ab40b513c 100644 --- a/doc/src/compute_hexorder_atom.txt +++ b/doc/src/compute_hexorder_atom.txt @@ -95,10 +95,9 @@ This compute calculates a per-atom array with 2 columns, giving the real and imaginary parts {qn}, a complex number restricted to the unit disk of the complex plane i.e. Re({qn})^2 + Im({qn})^2 <= 1 . -These values can be accessed by any command that uses -per-atom values from a compute as input. See "Section -6.15"_Section_howto.html#howto_15 for an overview of LAMMPS output -options. +These values can be accessed by any command that uses per-atom values +from a compute as input. See the "Howto output"_Howto_output.html doc +page for an overview of LAMMPS output options. [Restrictions:] none diff --git a/doc/src/compute_improper.txt b/doc/src/compute_improper.txt index f0d2fa400e..61c4f6cd29 100644 --- a/doc/src/compute_improper.txt +++ b/doc/src/compute_improper.txt @@ -37,8 +37,8 @@ This compute calculates a global vector of length N where N is the number of sub_styles defined by the "improper_style hybrid"_improper_style.html command. which can be accessed by indices 1-N. These values can be used by any command that uses global scalar -or vector values from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output +or vector values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. The vector values are "extensive" and will be in energy diff --git a/doc/src/compute_improper_local.txt b/doc/src/compute_improper_local.txt index 0c289fbf07..2aec554d2f 100644 --- a/doc/src/compute_improper_local.txt +++ b/doc/src/compute_improper_local.txt @@ -63,8 +63,8 @@ array is the number of impropers. If a single keyword is specified, a local vector is produced. If two or more keywords are specified, a local array is produced where the number of columns = the number of keywords. The vector or array can be accessed by any command that -uses local values from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output +uses local values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. The output for {chi} will be in degrees. diff --git a/doc/src/compute_inertia_chunk.txt b/doc/src/compute_inertia_chunk.txt index b0dbb12aea..3edd25d69b 100644 --- a/doc/src/compute_inertia_chunk.txt +++ b/doc/src/compute_inertia_chunk.txt @@ -30,10 +30,9 @@ chunk/atom"_compute_chunk_atom.html command, which assigns each atom to a single chunk (or no chunk). The ID for this command is specified as chunkID. For example, a single chunk could be the atoms in a molecule or atoms in a spatial bin. See the "compute -chunk/atom"_compute_chunk_atom.html doc page and "Section -6.23"_Section_howto.html#howto_23 for details of how chunks can be -defined and examples of how they can be used to measure properties of -a system. +chunk/atom"_compute_chunk_atom.html and "Howto chunk"_Howto_chunk.html +doc pages for details of how chunks can be defined and examples of how +they can be used to measure properties of a system. This compute calculates the 6 components of the symmetric inertia tensor for each chunk, ordered Ixx,Iyy,Izz,Ixy,Iyz,Ixz. The @@ -72,8 +71,8 @@ number of chunks {Nchunk} as calculated by the specified "compute chunk/atom"_compute_chunk_atom.html command. The number of columns = 6 for the 6 components of the inertia tensor for each chunk, ordered as listed above. These values can be accessed by any command that -uses global array values from a compute as input. See "Section -6.15"_Section_howto.html#howto_15 for an overview of LAMMPS output +uses global array values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. The array values are "intensive". The array values will be in diff --git a/doc/src/compute_ke.txt b/doc/src/compute_ke.txt index caee897162..d6f4e1b709 100644 --- a/doc/src/compute_ke.txt +++ b/doc/src/compute_ke.txt @@ -44,7 +44,7 @@ include different degrees of freedom (translational, rotational, etc). This compute calculates a global scalar (the summed KE). This value can be used by any command that uses a global scalar value from a -compute as input. See "Section 6.15"_Section_howto.html#howto_15 +compute as input. See the "Howto output"_Howto_output.html doc page for an overview of LAMMPS output options. The scalar value calculated by this compute is "extensive". The diff --git a/doc/src/compute_ke_atom.txt b/doc/src/compute_ke_atom.txt index f5431f0569..e0e96a80d8 100644 --- a/doc/src/compute_ke_atom.txt +++ b/doc/src/compute_ke_atom.txt @@ -34,7 +34,7 @@ specified compute group. This compute calculates a per-atom vector, which can be accessed by any command that uses per-atom values from a compute as input. See -"Section 6.15"_Section_howto.html#howto_15 for an overview of +the "Howto output"_Howto_output.html doc page for an overview of LAMMPS output options. The per-atom vector values will be in energy "units"_units.html. diff --git a/doc/src/compute_ke_atom_eff.txt b/doc/src/compute_ke_atom_eff.txt index 8228e13f07..aa188a411b 100644 --- a/doc/src/compute_ke_atom_eff.txt +++ b/doc/src/compute_ke_atom_eff.txt @@ -57,9 +57,9 @@ electrons) not in the specified compute group. [Output info:] This compute calculates a scalar quantity for each atom, which can be -accessed by any command that uses per-atom computes as input. See -"Section 6.15"_Section_howto.html#howto_15 for an overview of -LAMMPS output options. +accessed by any command that uses per-atom computes as input. See the +"Howto output"_Howto_output.html doc page for an overview of LAMMPS +output options. The per-atom vector values will be in energy "units"_units.html. diff --git a/doc/src/compute_ke_eff.txt b/doc/src/compute_ke_eff.txt index ac8d7e6c01..334b4121ed 100644 --- a/doc/src/compute_ke_eff.txt +++ b/doc/src/compute_ke_eff.txt @@ -61,7 +61,7 @@ See "compute temp/eff"_compute_temp_eff.html. This compute calculates a global scalar (the KE). This value can be used by any command that uses a global scalar value from a compute as -input. See "Section 6.15"_Section_howto.html#howto_15 for an +input. See the "Howto output"_Howto_output.html doc page for an overview of LAMMPS output options. The scalar value calculated by this compute is "extensive". The diff --git a/doc/src/compute_ke_rigid.txt b/doc/src/compute_ke_rigid.txt index f79696a77a..69cf4a598e 100644 --- a/doc/src/compute_ke_rigid.txt +++ b/doc/src/compute_ke_rigid.txt @@ -40,8 +40,8 @@ calculation. This compute calculates a global scalar (the summed KE of all the rigid bodies). This value can be used by any command that uses a -global scalar value from a compute as input. See "Section -6.15"_Section_howto.html#howto_15 for an overview of LAMMPS output +global scalar value from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. The scalar value calculated by this compute is "extensive". The diff --git a/doc/src/compute_meso_e_atom.txt b/doc/src/compute_meso_e_atom.txt index 4e621b4301..70a8969386 100644 --- a/doc/src/compute_meso_e_atom.txt +++ b/doc/src/compute_meso_e_atom.txt @@ -38,7 +38,7 @@ specified compute group. This compute calculates a per-atom vector, which can be accessed by any command that uses per-atom values from a compute as input. See -"Section 6.15"_Section_howto.html#howto_15 for an overview of +the "Howto output"_Howto_output.html doc page for an overview of LAMMPS output options. The per-atom vector values will be in energy "units"_units.html. diff --git a/doc/src/compute_meso_rho_atom.txt b/doc/src/compute_meso_rho_atom.txt index a017424dd0..912587f4a2 100644 --- a/doc/src/compute_meso_rho_atom.txt +++ b/doc/src/compute_meso_rho_atom.txt @@ -38,7 +38,7 @@ specified compute group. This compute calculates a per-atom vector, which can be accessed by any command that uses per-atom values from a compute as input. See -"Section 6.15"_Section_howto.html#howto_15 for an overview of +the "Howto output"_Howto_output.html doc page for an overview of LAMMPS output options. The per-atom vector values will be in mass/volume "units"_units.html. diff --git a/doc/src/compute_meso_t_atom.txt b/doc/src/compute_meso_t_atom.txt index 9e81b038f4..c9db9bf50e 100644 --- a/doc/src/compute_meso_t_atom.txt +++ b/doc/src/compute_meso_t_atom.txt @@ -40,7 +40,7 @@ specified compute group. This compute calculates a per-atom vector, which can be accessed by any command that uses per-atom values from a compute as input. See -"Section 6.15"_Section_howto.html#howto_15 for an overview of +the "Howto output"_Howto_output.html doc page for an overview of LAMMPS output options. The per-atom vector values will be in temperature "units"_units.html. diff --git a/doc/src/compute_msd.txt b/doc/src/compute_msd.txt index f806c5e292..742f7ce113 100644 --- a/doc/src/compute_msd.txt +++ b/doc/src/compute_msd.txt @@ -93,9 +93,8 @@ instead of many, which will change the values of msd somewhat. This compute calculates a global vector of length 4, which can be accessed by indices 1-4 by any command that uses global vector values -from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output -options. +from a compute as input. See the "Howto output"_Howto_output.html doc +page for an overview of LAMMPS output options. The vector values are "intensive". The vector values will be in distance^2 "units"_units.html. diff --git a/doc/src/compute_msd_chunk.txt b/doc/src/compute_msd_chunk.txt index 7f31b61ed0..3e1d8542ae 100644 --- a/doc/src/compute_msd_chunk.txt +++ b/doc/src/compute_msd_chunk.txt @@ -30,10 +30,9 @@ chunk/atom"_compute_chunk_atom.html command, which assigns each atom to a single chunk (or no chunk). The ID for this command is specified as chunkID. For example, a single chunk could be the atoms in a molecule or atoms in a spatial bin. See the "compute -chunk/atom"_compute_chunk_atom.html doc page and "Section -6.23"_Section_howto.html#howto_23 for details of how chunks can be -defined and examples of how they can be used to measure properties of -a system. +chunk/atom"_compute_chunk_atom.html and "Howto chunk"_Howto_chunk.html +doc pages for details of how chunks can be defined and examples of how +they can be used to measure properties of a system. Four quantities are calculated by this compute for each chunk. The first 3 quantities are the squared dx,dy,dz displacements of the @@ -106,7 +105,7 @@ number of chunks {Nchunk} as calculated by the specified "compute chunk/atom"_compute_chunk_atom.html command. The number of columns = 4 for dx,dy,dz and the total displacement. These values can be accessed by any command that uses global array values from a compute -as input. See "this section"_Section_howto.html#howto_15 for an +as input. See the "Howto output"_Howto_output.html doc page for an overview of LAMMPS output options. The array values are "intensive". The array values will be in diff --git a/doc/src/compute_msd_nongauss.txt b/doc/src/compute_msd_nongauss.txt index 198da999e0..db8788db0b 100644 --- a/doc/src/compute_msd_nongauss.txt +++ b/doc/src/compute_msd_nongauss.txt @@ -57,9 +57,8 @@ NOTEs, which also apply to this compute. This compute calculates a global vector of length 3, which can be accessed by indices 1-3 by any command that uses global vector values -from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output -options. +from a compute as input. See the "Howto output"_Howto_output.html doc +page for an overview of LAMMPS output options. The vector values are "intensive". The first vector value will be in distance^2 "units"_units.html, the second is in distance^4 units, and diff --git a/doc/src/compute_omega_chunk.txt b/doc/src/compute_omega_chunk.txt index 46c72d3dcb..4a7a996d1d 100644 --- a/doc/src/compute_omega_chunk.txt +++ b/doc/src/compute_omega_chunk.txt @@ -30,10 +30,9 @@ chunk/atom"_compute_chunk_atom.html command, which assigns each atom to a single chunk (or no chunk). The ID for this command is specified as chunkID. For example, a single chunk could be the atoms in a molecule or atoms in a spatial bin. See the "compute -chunk/atom"_compute_chunk_atom.html doc page and "Section -6.23"_Section_howto.html#howto_23 for details of how chunks can be -defined and examples of how they can be used to measure properties of -a system. +chunk/atom"_compute_chunk_atom.html and "Howto chunk"_Howto_chunk.html +doc pages for details of how chunks can be defined and examples of how +they can be used to measure properties of a system. This compute calculates the 3 components of the angular velocity vector for each chunk, via the formula L = Iw where L is the angular @@ -73,8 +72,8 @@ number of chunks {Nchunk} as calculated by the specified "compute chunk/atom"_compute_chunk_atom.html command. The number of columns = 3 for the 3 xyz components of the angular velocity for each chunk. These values can be accessed by any command that uses global array -values from a compute as input. See "Section -6.15"_Section_howto.html#howto_15 for an overview of LAMMPS output +values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. The array values are "intensive". The array values will be in diff --git a/doc/src/compute_orientorder_atom.txt b/doc/src/compute_orientorder_atom.txt index adf11dcfcf..a8b4008012 100644 --- a/doc/src/compute_orientorder_atom.txt +++ b/doc/src/compute_orientorder_atom.txt @@ -115,10 +115,9 @@ Re({Ybar_-m+1}) Im({Ybar_-m+1}) ... Re({Ybar_m}) Im({Ybar_m}). This way, the per-atom array will have a total of {nlvalues}+2*(2{l}+1) columns. -These values can be accessed by any command that uses -per-atom values from a compute as input. See "Section -6.15"_Section_howto.html#howto_15 for an overview of LAMMPS output -options. +These values can be accessed by any command that uses per-atom values +from a compute as input. See the "Howto output"_Howto_output.html doc +page for an overview of LAMMPS output options. [Restrictions:] none diff --git a/doc/src/compute_pair.txt b/doc/src/compute_pair.txt index 0602dab81b..be40d7a550 100644 --- a/doc/src/compute_pair.txt +++ b/doc/src/compute_pair.txt @@ -62,9 +62,8 @@ This compute calculates a global scalar which is {epair} or {evdwl} or {ecoul}. If the pair style supports it, it also calculates a global vector of length >= 1, as determined by the pair style. These values can be used by any command that uses global scalar or vector values -from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output -options. +from a compute as input. See the "Howto output"_Howto_output.html doc +page for an overview of LAMMPS output options. The scalar and vector values calculated by this compute are "extensive". diff --git a/doc/src/compute_pair_local.txt b/doc/src/compute_pair_local.txt index 16aaba4667..bbbc5823f2 100644 --- a/doc/src/compute_pair_local.txt +++ b/doc/src/compute_pair_local.txt @@ -119,8 +119,8 @@ array is the number of pairs. If a single keyword is specified, a local vector is produced. If two or more keywords are specified, a local array is produced where the number of columns = the number of keywords. The vector or array can be accessed by any command that -uses local values from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output +uses local values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. The output for {dist} will be in distance "units"_units.html. The diff --git a/doc/src/compute_pe.txt b/doc/src/compute_pe.txt index 15f27a8eff..f3ce5678b0 100644 --- a/doc/src/compute_pe.txt +++ b/doc/src/compute_pe.txt @@ -64,9 +64,8 @@ See the "thermo_style" command for more details. This compute calculates a global scalar (the potential energy). This value can be used by any command that uses a global scalar value from -a compute as input. See "Section -6.15"_Section_howto.html#howto_15 for an overview of LAMMPS output -options. +a compute as input. See the "Howto output"_Howto_output.html doc page +for an overview of LAMMPS output options. The scalar value calculated by this compute is "extensive". The scalar value will be in energy "units"_units.html. diff --git a/doc/src/compute_pe_atom.txt b/doc/src/compute_pe_atom.txt index c312c886a6..e6bc5f9052 100644 --- a/doc/src/compute_pe_atom.txt +++ b/doc/src/compute_pe_atom.txt @@ -81,7 +81,7 @@ global system energy. This compute calculates a per-atom vector, which can be accessed by any command that uses per-atom values from a compute as input. See -"Section 6.15"_Section_howto.html#howto_15 for an overview of +the "Howto output"_Howto_output.html doc page for an overview of LAMMPS output options. The per-atom vector values will be in energy "units"_units.html. diff --git a/doc/src/compute_plasticity_atom.txt b/doc/src/compute_plasticity_atom.txt index 788213fc65..c992ca8200 100644 --- a/doc/src/compute_plasticity_atom.txt +++ b/doc/src/compute_plasticity_atom.txt @@ -41,8 +41,9 @@ compute group. [Output info:] This compute calculates a per-atom vector, which can be accessed by -any command that uses per-atom values from a compute as input. See -Section_howto 15 for an overview of LAMMPS output options. +any command that uses per-atom values from a compute as input. See +the "Howto output"_Howto_output.html doc page for an overview of +LAMMPS output options. The per-atom vector values are unitless numbers (lambda) >= 0.0. diff --git a/doc/src/compute_pressure.txt b/doc/src/compute_pressure.txt index 8b7491da49..51d3241ace 100644 --- a/doc/src/compute_pressure.txt +++ b/doc/src/compute_pressure.txt @@ -129,8 +129,8 @@ instructions on how to use the accelerated styles effectively. This compute calculates a global scalar (the pressure) and a global vector of length 6 (pressure tensor), which can be accessed by indices 1-6. These values can be used by any command that uses global scalar -or vector values from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output +or vector values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. The scalar and vector values calculated by this compute are diff --git a/doc/src/compute_property_atom.txt b/doc/src/compute_property_atom.txt index c0970d5121..88bdf5a453 100644 --- a/doc/src/compute_property_atom.txt +++ b/doc/src/compute_property_atom.txt @@ -93,11 +93,11 @@ compute 3 all property/atom sp spx spy spz :pre Define a computation that simply stores atom attributes for each atom in the group. This is useful so that the values can be used by other -"output commands"_Section_howto.html#howto_15 that take computes as -inputs. See for example, the "compute reduce"_compute_reduce.html, -"fix ave/atom"_fix_ave_atom.html, "fix ave/histo"_fix_ave_histo.html, -"fix ave/chunk"_fix_ave_chunk.html, and "atom-style -variable"_variable.html commands. +"output commands"_Howto_output.html that take computes as inputs. See +for example, the "compute reduce"_compute_reduce.html, "fix +ave/atom"_fix_ave_atom.html, "fix ave/histo"_fix_ave_histo.html, "fix +ave/chunk"_fix_ave_chunk.html, and "atom-style variable"_variable.html +commands. The list of possible attributes is the same as that used by the "dump custom"_dump.html command, which describes their meaning, with some @@ -149,8 +149,8 @@ on the number of input values. If a single input is specified, a per-atom vector is produced. If two or more inputs are specified, a per-atom array is produced where the number of columns = the number of inputs. The vector or array can be accessed by any command that uses -per-atom values from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output +per-atom values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. The vector or array values will be in whatever "units"_units.html the diff --git a/doc/src/compute_property_chunk.txt b/doc/src/compute_property_chunk.txt index b9d4944b30..ad131a8a60 100644 --- a/doc/src/compute_property_chunk.txt +++ b/doc/src/compute_property_chunk.txt @@ -36,15 +36,14 @@ chunk/atom"_compute_chunk_atom.html command, which assigns each atom to a single chunk (or no chunk). The ID for this command is specified as chunkID. For example, a single chunk could be the atoms in a molecule or atoms in a spatial bin. See the "compute -chunk/atom"_compute_chunk_atom.html doc page and "Section -6.23"_Section_howto.html#howto_23 for details of how chunks can be -defined and examples of how they can be used to measure properties of -a system. +chunk/atom"_compute_chunk_atom.html and "Howto chunk"_Howto_chunk.html +doc pages for details of how chunks can be defined and examples of how +they can be used to measure properties of a system. This compute calculates and stores the specified attributes of chunks as global data so they can be accessed by other "output -commands"_Section_howto.html#howto_15 and used in conjunction with -other commands that generate per-chunk data, such as "compute +commands"_Howto_output.html and used in conjunction with other +commands that generate per-chunk data, such as "compute com/chunk"_compute_com_chunk.html or "compute msd/chunk"_compute_msd_chunk.html. @@ -103,8 +102,8 @@ single input is specified, a global vector is produced. If two or more inputs are specified, a global array is produced where the number of columns = the number of inputs. The vector or array can be accessed by any command that uses global values from a compute as -input. See "this section"_Section_howto.html#howto_15 for an overview -of LAMMPS output options. +input. See the "Howto output"_Howto_output.html doc page for an +overview of LAMMPS output options. The vector or array values are "intensive". The values will be unitless or in the units discussed above. diff --git a/doc/src/compute_property_local.txt b/doc/src/compute_property_local.txt index 39106a39c8..74595f00f6 100644 --- a/doc/src/compute_property_local.txt +++ b/doc/src/compute_property_local.txt @@ -48,10 +48,10 @@ compute 1 all property/local atype aatom2 :pre Define a computation that stores the specified attributes as local data so it can be accessed by other "output -commands"_Section_howto.html#howto_15. If the input attributes refer -to bond information, then the number of datums generated, aggregated -across all processors, equals the number of bonds in the system. -Ditto for pairs, angles, etc. +commands"_Howto_output.html. If the input attributes refer to bond +information, then the number of datums generated, aggregated across +all processors, equals the number of bonds in the system. Ditto for +pairs, angles, etc. If multiple attributes are specified then they must all generate the same amount of information, so that the resulting local array has the @@ -140,8 +140,8 @@ the array is the number of bonds, angles, etc. If a single input is specified, a local vector is produced. If two or more inputs are specified, a local array is produced where the number of columns = the number of inputs. The vector or array can be accessed by any command -that uses local values from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output +that uses local values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. The vector or array values will be integers that correspond to the diff --git a/doc/src/compute_rdf.txt b/doc/src/compute_rdf.txt index e462e85fc0..c2d2c379fe 100644 --- a/doc/src/compute_rdf.txt +++ b/doc/src/compute_rdf.txt @@ -152,7 +152,7 @@ coordinate (center of the bin), Each successive set of 2 columns has the g(r) and coord(r) values for a specific set of {itypeN} versus {jtypeN} interactions, as described above. These values can be used by any command that uses a global values from a compute as input. See -"Section 6.15"_Section_howto.html#howto_15 for an overview of +the "Howto output"_Howto_output.html doc page for an overview of LAMMPS output options. The array values calculated by this compute are all "intensive". diff --git a/doc/src/compute_reduce.txt b/doc/src/compute_reduce.txt index 48115a0886..614ef50581 100644 --- a/doc/src/compute_reduce.txt +++ b/doc/src/compute_reduce.txt @@ -192,7 +192,7 @@ This compute calculates a global scalar if a single input value is specified or a global vector of length N where N is the number of inputs, and which can be accessed by indices 1 to N. These values can be used by any command that uses global scalar or vector values from a -compute as input. See "Section 6.15"_Section_howto.html#howto_15 +compute as input. See the "Howto output"_Howto_output.html doc page for an overview of LAMMPS output options. All the scalar or vector values calculated by this compute are diff --git a/doc/src/compute_rigid_local.txt b/doc/src/compute_rigid_local.txt index 077ad57d81..380713d091 100644 --- a/doc/src/compute_rigid_local.txt +++ b/doc/src/compute_rigid_local.txt @@ -49,8 +49,8 @@ Define a computation that simply stores rigid body attributes for rigid bodies defined by the "fix rigid/small"_fix_rigid.html command or one of its NVE, NVT, NPT, NPH variants. The data is stored as local data so it can be accessed by other "output -commands"_Section_howto.html#howto_15 that process local data, such as -the "compute reduce"_compute_reduce.html or "dump local"_dump.html +commands"_Howto_output.html that process local data, such as the +"compute reduce"_compute_reduce.html or "dump local"_dump.html commands. Note that this command only works with the "fix @@ -154,9 +154,9 @@ array is the number of rigid bodies. If a single keyword is specified, a local vector is produced. If two or more keywords are specified, a local array is produced where the number of columns = the number of keywords. The vector or array can be accessed by any -command that uses local values from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output -options. +command that uses local values from a compute as input. See the +"Howto output"_Howto_output.html doc page for an overview of LAMMPS +output options. The vector or array values will be in whatever "units"_units.html the corresponding attribute is in: diff --git a/doc/src/compute_saed.txt b/doc/src/compute_saed.txt index 020f72f565..419ad3c489 100644 --- a/doc/src/compute_saed.txt +++ b/doc/src/compute_saed.txt @@ -143,10 +143,9 @@ the number of reciprocal lattice nodes that are explored by the mesh. The entries of the global vector are the computed diffraction intensities as described above. -The vector can be accessed by any command that uses global values -from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output -options. +The vector can be accessed by any command that uses global values from +a compute as input. See the "Howto output"_Howto_output.html doc page +for an overview of LAMMPS output options. All array values calculated by this compute are "intensive". diff --git a/doc/src/compute_slice.txt b/doc/src/compute_slice.txt index 13f40ecf92..69eb7976ad 100644 --- a/doc/src/compute_slice.txt +++ b/doc/src/compute_slice.txt @@ -94,8 +94,8 @@ specified or a global array with N columns where N is the number of inputs. The length of the vector or the number of rows in the array is equal to the number of values extracted from each input vector. These values can be used by any command that uses global vector or -array values from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output +array values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. The vector or array values calculated by this compute are simply diff --git a/doc/src/compute_smd_contact_radius.txt b/doc/src/compute_smd_contact_radius.txt index 69fe453343..5e043a1390 100644 --- a/doc/src/compute_smd_contact_radius.txt +++ b/doc/src/compute_smd_contact_radius.txt @@ -35,9 +35,9 @@ specified compute group. [Output info:] -This compute calculates a per-particle vector, which can be accessed by -any command that uses per-particle values from a compute as input. See -"Section 6.15"_Section_howto.html#howto_15 for an overview of +This compute calculates a per-particle vector, which can be accessed +by any command that uses per-particle values from a compute as input. +See the "Howto output"_Howto_output.html doc page for an overview of LAMMPS output options. The per-particle vector values will be in distance "units"_units.html. diff --git a/doc/src/compute_smd_damage.txt b/doc/src/compute_smd_damage.txt index b6c75a3b20..ea814ba064 100644 --- a/doc/src/compute_smd_damage.txt +++ b/doc/src/compute_smd_damage.txt @@ -28,10 +28,10 @@ See "this PDF guide"_PDF/SMD_LAMMPS_userguide.pdf to use Smooth Mach Dynamics in [Output Info:] -This compute calculates a per-particle vector, which can be accessed by -any command that uses per-particle values from a compute as input. See -"How-to discussions, section 6.15"_Section_howto.html#howto_15 -for an overview of LAMMPS output options. +This compute calculates a per-particle vector, which can be accessed +by any command that uses per-particle values from a compute as input. +See the "Howto output"_Howto_output.html doc page for an overview of +LAMMPS output options. The per-particle values are dimensionless an in the range of zero to one. diff --git a/doc/src/compute_smd_hourglass_error.txt b/doc/src/compute_smd_hourglass_error.txt index a15b79e64e..046f7e7f27 100644 --- a/doc/src/compute_smd_hourglass_error.txt +++ b/doc/src/compute_smd_hourglass_error.txt @@ -37,10 +37,10 @@ Mach Dynamics in LAMMPS. [Output Info:] -This compute calculates a per-particle vector, which can be accessed by -any command that uses per-particle values from a compute as input. See -"How-to discussions, section 6.15"_Section_howto.html#howto_15 -for an overview of LAMMPS output options. +This compute calculates a per-particle vector, which can be accessed +by any command that uses per-particle values from a compute as input. +See the "Howto output"_Howto_output.html doc page for an overview of +LAMMPS output options. The per-particle vector values will are dimensionless. See "units"_units.html. diff --git a/doc/src/compute_smd_internal_energy.txt b/doc/src/compute_smd_internal_energy.txt index bc6f9e0f20..b88bd8a1ce 100644 --- a/doc/src/compute_smd_internal_energy.txt +++ b/doc/src/compute_smd_internal_energy.txt @@ -31,8 +31,8 @@ Mach Dynamics in LAMMPS. This compute calculates a per-particle vector, which can be accessed by any command that uses per-particle values from a compute as input. -See "How-to discussions, section 6.15"_Section_howto.html#howto_15 for -an overview of LAMMPS output options. +See the "Howto output"_Howto_output.html doc page for an overview of +LAMMPS output options. The per-particle vector values will be given in "units"_units.html of energy. diff --git a/doc/src/compute_smd_plastic_strain.txt b/doc/src/compute_smd_plastic_strain.txt index af5b164453..7fd083726f 100644 --- a/doc/src/compute_smd_plastic_strain.txt +++ b/doc/src/compute_smd_plastic_strain.txt @@ -32,8 +32,8 @@ Mach Dynamics in LAMMPS. This compute calculates a per-particle vector, which can be accessed by any command that uses per-particle values from a compute as input. -See "How-to discussions, section 6.15"_Section_howto.html#howto_15 for -an overview of LAMMPS output options. +See the "Howto output"_Howto_output.html doc page for an overview of +LAMMPS output options. The per-particle values will be given dimensionless. See "units"_units.html. diff --git a/doc/src/compute_smd_plastic_strain_rate.txt b/doc/src/compute_smd_plastic_strain_rate.txt index ba7b3176db..b17684e05e 100644 --- a/doc/src/compute_smd_plastic_strain_rate.txt +++ b/doc/src/compute_smd_plastic_strain_rate.txt @@ -32,8 +32,8 @@ Mach Dynamics in LAMMPS. This compute calculates a per-particle vector, which can be accessed by any command that uses per-particle values from a compute as input. -See "How-to discussions, section 6.15"_Section_howto.html#howto_15 for -an overview of LAMMPS output options. +See the "Howto output"_Howto_output.html doc page for an overview of +LAMMPS output options. The per-particle values will be given in "units"_units.html of one over time. diff --git a/doc/src/compute_smd_rho.txt b/doc/src/compute_smd_rho.txt index ae50526725..375513b9c7 100644 --- a/doc/src/compute_smd_rho.txt +++ b/doc/src/compute_smd_rho.txt @@ -33,8 +33,8 @@ Mach Dynamics in LAMMPS. This compute calculates a per-particle vector, which can be accessed by any command that uses per-particle values from a compute as input. -See "How-to discussions, section 6.15"_Section_howto.html#howto_15 for -an overview of LAMMPS output options. +See the "Howto output"_Howto_output.html doc page for an overview of +LAMMPS output options. The per-particle values will be in "units"_units.html of mass over volume. diff --git a/doc/src/compute_smd_tlsph_defgrad.txt b/doc/src/compute_smd_tlsph_defgrad.txt index 68b5dffa1c..d07ff99f07 100644 --- a/doc/src/compute_smd_tlsph_defgrad.txt +++ b/doc/src/compute_smd_tlsph_defgrad.txt @@ -32,9 +32,8 @@ Mach Dynamics in LAMMPS. This compute outputss a per-particle vector of vectors (tensors), which can be accessed by any command that uses per-particle values -from a compute as input. See "How-to discussions, section -6.15"_Section_howto.html#howto_15 for an overview of LAMMPS output -options. +from a compute as input. See the "Howto output"_Howto_output.html doc +page for an overview of LAMMPS output options. The per-particle vector values will be given dimensionless. See "units"_units.html. The per-particle vector has 10 entries. The first diff --git a/doc/src/compute_smd_tlsph_dt.txt b/doc/src/compute_smd_tlsph_dt.txt index 560a9b6fd8..798278661a 100644 --- a/doc/src/compute_smd_tlsph_dt.txt +++ b/doc/src/compute_smd_tlsph_dt.txt @@ -37,8 +37,8 @@ Mach Dynamics in LAMMPS. This compute calculates a per-particle vector, which can be accessed by any command that uses per-particle values from a compute as input. -See "How-to discussions, section 6.15"_Section_howto.html#howto_15 for -an overview of LAMMPS output options. +See the "Howto output"_Howto_output.html doc page for an overview of +LAMMPS output options. The per-particle values will be given in "units"_units.html of time. diff --git a/doc/src/compute_smd_tlsph_num_neighs.txt b/doc/src/compute_smd_tlsph_num_neighs.txt index 0420d1903d..632ab94208 100644 --- a/doc/src/compute_smd_tlsph_num_neighs.txt +++ b/doc/src/compute_smd_tlsph_num_neighs.txt @@ -32,8 +32,8 @@ Mach Dynamics in LAMMPS. This compute calculates a per-particle vector, which can be accessed by any command that uses per-particle values from a compute as input. -See "How-to discussions, section 6.15"_Section_howto.html#howto_15 for -an overview of LAMMPS output options. +See the "Howto output"_Howto_output.html doc page for an overview of +LAMMPS output options. The per-particle values are dimensionless. See "units"_units.html. diff --git a/doc/src/compute_smd_tlsph_shape.txt b/doc/src/compute_smd_tlsph_shape.txt index 02bd0c50dd..a3daf70222 100644 --- a/doc/src/compute_smd_tlsph_shape.txt +++ b/doc/src/compute_smd_tlsph_shape.txt @@ -33,9 +33,8 @@ Mach Dynamics in LAMMPS. This compute calculates a per-particle vector of vectors, which can be accessed by any command that uses per-particle values from a compute -as input. See "How-to discussions, section -6.15"_Section_howto.html#howto_15 for an overview of LAMMPS output -options. +as input. See the "Howto output"_Howto_output.html doc page for an +overview of LAMMPS output options. The per-particle vector has 7 entries. The first three entries correspond to the lengths of the ellipsoid's axes and have units of diff --git a/doc/src/compute_smd_tlsph_strain.txt b/doc/src/compute_smd_tlsph_strain.txt index f25d1b77db..899166359c 100644 --- a/doc/src/compute_smd_tlsph_strain.txt +++ b/doc/src/compute_smd_tlsph_strain.txt @@ -31,9 +31,8 @@ Mach Dynamics in LAMMPS. This compute calculates a per-particle vector of vectors (tensors), which can be accessed by any command that uses per-particle values -from a compute as input. See "How-to discussions, section -6.15"_Section_howto.html#howto_15 for an overview of LAMMPS output -options. +from a compute as input. See the "Howto output"_Howto_output.html doc +page for an overview of LAMMPS output options. The per-particle tensor values will be given dimensionless. See "units"_units.html. diff --git a/doc/src/compute_smd_tlsph_strain_rate.txt b/doc/src/compute_smd_tlsph_strain_rate.txt index 13ca57ac4d..29246a05d9 100644 --- a/doc/src/compute_smd_tlsph_strain_rate.txt +++ b/doc/src/compute_smd_tlsph_strain_rate.txt @@ -31,9 +31,8 @@ Mach Dynamics in LAMMPS. This compute calculates a per-particle vector of vectors (tensors), which can be accessed by any command that uses per-particle values -from a compute as input. See "How-to discussions, section -6.15"_Section_howto.html#howto_15 for an overview of LAMMPS output -options. +from a compute as input. See the "Howto output"_Howto_output.html doc +page for an overview of LAMMPS output options. The values will be given in "units"_units.html of one over time. diff --git a/doc/src/compute_smd_tlsph_stress.txt b/doc/src/compute_smd_tlsph_stress.txt index 5d707d4c2f..c2c23b6836 100644 --- a/doc/src/compute_smd_tlsph_stress.txt +++ b/doc/src/compute_smd_tlsph_stress.txt @@ -29,11 +29,10 @@ Mach Dynamics in LAMMPS. [Output info:] -This compute calculates a per-particle vector of vectors (tensors), which can be -accessed by any command that uses per-particle values from a compute -as input. See -"How-to discussions, section 6.15"_Section_howto.html#howto_15 -for an overview of LAMMPS output options. +This compute calculates a per-particle vector of vectors (tensors), +which can be accessed by any command that uses per-particle values +from a compute as input. See the "Howto output"_Howto_output.html doc +page for an overview of LAMMPS output options. The values will be given in "units"_units.html of pressure. diff --git a/doc/src/compute_smd_triangle_mesh_vertices.txt b/doc/src/compute_smd_triangle_mesh_vertices.txt index 5b0f0afc4c..3080ef700e 100644 --- a/doc/src/compute_smd_triangle_mesh_vertices.txt +++ b/doc/src/compute_smd_triangle_mesh_vertices.txt @@ -31,9 +31,9 @@ Mach Dynamics in LAMMPS. [Output info:] This compute returns a per-particle vector of vectors, which can be -accessed by any command that uses per-particle values from a compute as -input. See "How-to discussions, section 6.15"_Section_howto.html#howto_15 -for an overview of LAMMPS output options. +accessed by any command that uses per-particle values from a compute +as input. See the "Howto output"_Howto_output.html doc page for an +overview of LAMMPS output options. The per-particle vector has nine entries, (x1/y1/z1), (x2/y2/z2), and (x3/y3/z3) corresponding to the first, second, and third vertex of diff --git a/doc/src/compute_smd_ulsph_num_neighs.txt b/doc/src/compute_smd_ulsph_num_neighs.txt index adece93343..8550838799 100644 --- a/doc/src/compute_smd_ulsph_num_neighs.txt +++ b/doc/src/compute_smd_ulsph_num_neighs.txt @@ -32,7 +32,7 @@ Mach Dynamics in LAMMPS. This compute returns a per-particle vector, which can be accessed by any command that uses per-particle values from a compute as input. -See "Section 6.15"_Section_howto.html#howto_15 for an overview of +See the "Howto output"_Howto_output.html doc page for an overview of LAMMPS output options. The per-particle values will be given dimensionless, see "units"_units.html. diff --git a/doc/src/compute_smd_ulsph_strain.txt b/doc/src/compute_smd_ulsph_strain.txt index b7d425b12b..3813e61f6c 100644 --- a/doc/src/compute_smd_ulsph_strain.txt +++ b/doc/src/compute_smd_ulsph_strain.txt @@ -31,7 +31,7 @@ Mach Dynamics in LAMMPS. This compute calculates a per-particle tensor, which can be accessed by any command that uses per-particle values from a compute as input. -See "Section 6.15"_Section_howto.html#howto_15 for an overview of +See the "Howto output"_Howto_output.html doc page for an overview of LAMMPS output options. The per-particle vector has 6 entries, corresponding to the xx, yy, diff --git a/doc/src/compute_smd_ulsph_strain_rate.txt b/doc/src/compute_smd_ulsph_strain_rate.txt index e2c349c265..251e5ddbf7 100644 --- a/doc/src/compute_smd_ulsph_strain_rate.txt +++ b/doc/src/compute_smd_ulsph_strain_rate.txt @@ -32,9 +32,8 @@ Mach Dynamics in LAMMPS. This compute calculates a per-particle vector of vectors (tensors), which can be accessed by any command that uses per-particle values -from a compute as input. See "Section -6.15"_Section_howto.html#howto_15 for an overview of LAMMPS output -options. +from a compute as input. See the "Howto output"_Howto_output.html doc +page for an overview of LAMMPS output options. The values will be given in "units"_units.html of one over time. diff --git a/doc/src/compute_smd_ulsph_stress.txt b/doc/src/compute_smd_ulsph_stress.txt index 47f903d3b8..719cf006c9 100644 --- a/doc/src/compute_smd_ulsph_stress.txt +++ b/doc/src/compute_smd_ulsph_stress.txt @@ -30,9 +30,8 @@ Mach Dynamics in LAMMPS. This compute calculates a per-particle vector of vectors (tensors), which can be accessed by any command that uses per-particle values -from a compute as input. See "Section -6.15"_Section_howto.html#howto_15 for an overview of LAMMPS output -options. +from a compute as input. See the "Howto output"_Howto_output.html doc +page for an overview of LAMMPS output options. The values will be given in "units"_units.html of pressure. diff --git a/doc/src/compute_smd_vol.txt b/doc/src/compute_smd_vol.txt index fc736a5bf5..495c09a5f5 100644 --- a/doc/src/compute_smd_vol.txt +++ b/doc/src/compute_smd_vol.txt @@ -31,8 +31,8 @@ Mach Dynamics in LAMMPS. This compute calculates a per-particle vector, which can be accessed by any command that uses per-particle values from a compute as input. -See "How-to discussions, section 6.15"_Section_howto.html#howto_15 for -an overview of LAMMPS output options. +See the "Howto output"_Howto_output.html doc page for an overview of +LAMMPS output options. The per-particle vector values will be given in "units"_units.html of volume. diff --git a/doc/src/compute_sna_atom.txt b/doc/src/compute_sna_atom.txt index 268e23ac28..6fdd85568b 100644 --- a/doc/src/compute_sna_atom.txt +++ b/doc/src/compute_sna_atom.txt @@ -244,9 +244,8 @@ So the nesting order from inside to outside is bispectrum component, linear then quadratic, vector/tensor component, type. These values can be accessed by any command that uses per-atom values -from a compute as input. See "Section -6.15"_Section_howto.html#howto_15 for an overview of LAMMPS output -options. +from a compute as input. See the "Howto output"_Howto_output.html doc +page for an overview of LAMMPS output options. [Restrictions:] diff --git a/doc/src/compute_stress_atom.txt b/doc/src/compute_stress_atom.txt index 83b1df68e3..423c1dcfda 100644 --- a/doc/src/compute_stress_atom.txt +++ b/doc/src/compute_stress_atom.txt @@ -142,9 +142,8 @@ global system pressure. This compute calculates a per-atom array with 6 columns, which can be accessed by indices 1-6 by any command that uses per-atom values from -a compute as input. See "Section -6.15"_Section_howto.html#howto_15 for an overview of LAMMPS output -options. +a compute as input. See the "Howto output"_Howto_output.html doc page +for an overview of LAMMPS output options. The per-atom array values will be in pressure*volume "units"_units.html as discussed above. diff --git a/doc/src/compute_tdpd_cc_atom.txt b/doc/src/compute_tdpd_cc_atom.txt index a6a12dc52c..ec077a33d1 100644 --- a/doc/src/compute_tdpd_cc_atom.txt +++ b/doc/src/compute_tdpd_cc_atom.txt @@ -33,9 +33,9 @@ details see "(Li2015)"_#Li2015a. [Output info:] This compute calculates a per-atom vector, which can be accessed by -any command that uses per-atom values from a compute as input. See -"Section 6.15"_Section_howto.html#howto_15 for an overview of -LAMMPS output options. +any command that uses per-atom values from a compute as input. See the +"Howto output"_Howto_output.html doc page for an overview of LAMMPS +output options. The per-atom vector values will be in the units of chemical species per unit mass. diff --git a/doc/src/compute_temp.txt b/doc/src/compute_temp.txt index f9fa56c882..cce40261c6 100644 --- a/doc/src/compute_temp.txt +++ b/doc/src/compute_temp.txt @@ -58,8 +58,8 @@ compute thermo_temp all temp :pre See the "thermo_style" command for more details. -See "this howto section"_Section_howto.html#howto_16 of the manual for -a discussion of different ways to compute temperature and perform +See the "Howto thermostat"_Howto_thermostat.html doc page for a +discussion of different ways to compute temperature and perform thermostatting. :line @@ -91,8 +91,8 @@ instructions on how to use the accelerated styles effectively. This compute calculates a global scalar (the temperature) and a global vector of length 6 (KE tensor), which can be accessed by indices 1-6. These values can be used by any command that uses global scalar or -vector values from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output +vector values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. The scalar value calculated by this compute is "intensive". The diff --git a/doc/src/compute_temp_asphere.txt b/doc/src/compute_temp_asphere.txt index 495366b345..a5fc0e8927 100644 --- a/doc/src/compute_temp_asphere.txt +++ b/doc/src/compute_temp_asphere.txt @@ -93,8 +93,8 @@ computed correctly. If needed, the subtracted degrees-of-freedom can be altered using the {extra} option of the "compute_modify"_compute_modify.html command. -See "this howto section"_Section_howto.html#howto_16 of the manual for -a discussion of different ways to compute temperature and perform +See the "Howto thermostat"_Howto_thermostat.html doc page for a +discussion of different ways to compute temperature and perform thermostatting. :line @@ -122,8 +122,8 @@ rotational degrees of freedom. This compute calculates a global scalar (the temperature) and a global vector of length 6 (KE tensor), which can be accessed by indices 1-6. These values can be used by any command that uses global scalar or -vector values from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output +vector values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. The scalar value calculated by this compute is "intensive". The diff --git a/doc/src/compute_temp_body.txt b/doc/src/compute_temp_body.txt index f72b886cc4..580564b059 100644 --- a/doc/src/compute_temp_body.txt +++ b/doc/src/compute_temp_body.txt @@ -75,8 +75,8 @@ computed correctly. If needed, the subtracted degrees-of-freedom can be altered using the {extra} option of the "compute_modify"_compute_modify.html command. -See "this howto section"_Section_howto.html#howto_16 of the manual for -a discussion of different ways to compute temperature and perform +See the "Howto thermostat"_Howto_thermostat.html doc page for a +discussion of different ways to compute temperature and perform thermostatting. :line @@ -104,8 +104,8 @@ rotational degrees of freedom. This compute calculates a global scalar (the temperature) and a global vector of length 6 (KE tensor), which can be accessed by indices 1-6. These values can be used by any command that uses global scalar or -vector values from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output +vector values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. The scalar value calculated by this compute is "intensive". The diff --git a/doc/src/compute_temp_chunk.txt b/doc/src/compute_temp_chunk.txt index f877f6ece8..5d7d64ce68 100644 --- a/doc/src/compute_temp_chunk.txt +++ b/doc/src/compute_temp_chunk.txt @@ -52,10 +52,9 @@ chunk/atom"_compute_chunk_atom.html command, which assigns each atom to a single chunk (or no chunk). The ID for this command is specified as chunkID. For example, a single chunk could be the atoms in a molecule or atoms in a spatial bin. See the "compute -chunk/atom"_compute_chunk_atom.html doc page and "Section -6.23"_Section_howto.html#howto_23 for details of how chunks can be -defined and examples of how they can be used to measure properties of -a system. +chunk/atom"_compute_chunk_atom.html and "Howto chunk"_Howto_chunk.html +doc pages for details of how chunks can be defined and examples of how +they can be used to measure properties of a system. The temperature is calculated by the formula KE = DOF/2 k T, where KE = total kinetic energy of all atoms assigned to chunks (sum of 1/2 m @@ -200,8 +199,8 @@ molecule. This compute calculates a global scalar (the temperature) and a global vector of length 6 (KE tensor), which can be accessed by indices 1-6. These values can be used by any command that uses global scalar or -vector values from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output +vector values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. This compute also optionally calculates a global array, if one or more @@ -210,9 +209,8 @@ of the optional values are specified. The number of rows in the array "compute chunk/atom"_compute_chunk_atom.html command. The number of columns is the number of specified values (1 or more). These values can be accessed by any command that uses global array values from a -compute as input. Again, see "Section -6.15"_Section_howto.html#howto_15 for an overview of LAMMPS output -options. +compute as input. Again, see the "Howto output"_Howto_output.html doc +page for an overview of LAMMPS output options. The scalar value calculated by this compute is "intensive". The vector values are "extensive". The array values are "intensive". diff --git a/doc/src/compute_temp_com.txt b/doc/src/compute_temp_com.txt index c7cc5ec4e2..e8b46aec97 100644 --- a/doc/src/compute_temp_com.txt +++ b/doc/src/compute_temp_com.txt @@ -65,8 +65,8 @@ atoms that include these constraints will be computed correctly. If needed, the subtracted degrees-of-freedom can be altered using the {extra} option of the "compute_modify"_compute_modify.html command. -See "this howto section"_Section_howto.html#howto_16 of the manual for -a discussion of different ways to compute temperature and perform +See the "Howto thermostat"_Howto_thermostat.html doc page for a +discussion of different ways to compute temperature and perform thermostatting. [Output info:] @@ -74,8 +74,8 @@ thermostatting. This compute calculates a global scalar (the temperature) and a global vector of length 6 (KE tensor), which can be accessed by indices 1-6. These values can be used by any command that uses global scalar or -vector values from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output +vector values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. The scalar value calculated by this compute is "intensive". The diff --git a/doc/src/compute_temp_cs.txt b/doc/src/compute_temp_cs.txt index 561b787df6..9d2ceabd46 100644 --- a/doc/src/compute_temp_cs.txt +++ b/doc/src/compute_temp_cs.txt @@ -28,9 +28,9 @@ Define a computation that calculates the temperature of a system based on the center-of-mass velocity of atom pairs that are bonded to each other. This compute is designed to be used with the adiabatic core/shell model of "(Mitchell and Finchham)"_#MitchellFinchham1. See -"Section 6.25"_Section_howto.html#howto_25 of the manual for an -overview of the model as implemented in LAMMPS. Specifically, this -compute enables correct temperature calculation and thermostatting of +the "Howto coreshell"_Howto_coreshell.html doc page for an overview of +the model as implemented in LAMMPS. Specifically, this compute +enables correct temperature calculation and thermostatting of core/shell pairs where it is desirable for the internal degrees of freedom of the core/shell pairs to not be influenced by a thermostat. A compute of this style can be used by any command that computes a @@ -83,8 +83,9 @@ langevin"_fix_langevin.html. The internal energy of core/shell pairs can be calculated by the "compute temp/chunk"_compute_temp_chunk.html command, if chunks are -defined as core/shell pairs. See "Section -6.25"_Section_howto.html#howto_25 for more discussion on how to do this. +defined as core/shell pairs. See the "Howto +coreshell"_Howto_coreshell.html doc page doc page for more discussion +on how to do this. [Output info:] diff --git a/doc/src/compute_temp_deform.txt b/doc/src/compute_temp_deform.txt index 168b0b3880..b81d07babd 100644 --- a/doc/src/compute_temp_deform.txt +++ b/doc/src/compute_temp_deform.txt @@ -104,8 +104,8 @@ atoms that include these constraints will be computed correctly. If needed, the subtracted degrees-of-freedom can be altered using the {extra} option of the "compute_modify"_compute_modify.html command. -See "this howto section"_Section_howto.html#howto_16 of the manual for -a discussion of different ways to compute temperature and perform +See the "Howto thermostat"_Howto_thermostat.html doc page for a +discussion of different ways to compute temperature and perform thermostatting. [Output info:] @@ -113,8 +113,8 @@ thermostatting. This compute calculates a global scalar (the temperature) and a global vector of length 6 (KE tensor), which can be accessed by indices 1-6. These values can be used by any command that uses global scalar or -vector values from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output +vector values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. The scalar value calculated by this compute is "intensive". The diff --git a/doc/src/compute_temp_deform_eff.txt b/doc/src/compute_temp_deform_eff.txt index d09a0ace2f..418180d93c 100644 --- a/doc/src/compute_temp_deform_eff.txt +++ b/doc/src/compute_temp_deform_eff.txt @@ -48,8 +48,8 @@ component of the electrons is not affected. This compute calculates a global scalar (the temperature) and a global vector of length 6 (KE tensor), which can be accessed by indices 1-6. These values can be used by any command that uses global scalar or -vector values from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output +vector values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. The scalar value calculated by this compute is "intensive". The diff --git a/doc/src/compute_temp_drude.txt b/doc/src/compute_temp_drude.txt index 169b8d5880..3e86dc8fda 100644 --- a/doc/src/compute_temp_drude.txt +++ b/doc/src/compute_temp_drude.txt @@ -22,10 +22,10 @@ compute TDRUDE all temp/drude :pre [Description:] Define a computation that calculates the temperatures of core-Drude -pairs. This compute is designed to be used with the -"thermalized Drude oscillator model"_tutorial_drude.html. Polarizable -models in LAMMPS are described in "this -Section"_Section_howto.html#howto_25. +pairs. This compute is designed to be used with the "thermalized Drude +oscillator model"_Howto_drude.html. Polarizable models in LAMMPS +are described on the "Howto polarizable"_Howto_polarizable.html doc +page. Drude oscillators consist of a core particle and a Drude particle connected by a harmonic bond, and the relative motion of these Drude @@ -57,8 +57,8 @@ kinetic energy of the centers of mass (energy units) kinetic energy of the dipoles (energy units) :ol These values can be used by any command that uses global scalar or -vector values from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output +vector values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. Both the scalar value and the first two values of the vector diff --git a/doc/src/compute_temp_eff.txt b/doc/src/compute_temp_eff.txt index 409319edcb..42d22a33a7 100644 --- a/doc/src/compute_temp_eff.txt +++ b/doc/src/compute_temp_eff.txt @@ -69,8 +69,8 @@ atoms that include these constraints will be computed correctly. If needed, the subtracted degrees-of-freedom can be altered using the {extra} option of the "compute_modify"_compute_modify.html command. -See "this howto section"_Section_howto.html#howto_16 of the manual for -a discussion of different ways to compute temperature and perform +See the "Howto thermostat"_Howto_thermostat.html doc page for a +discussion of different ways to compute temperature and perform thermostatting. [Output info:] diff --git a/doc/src/compute_temp_partial.txt b/doc/src/compute_temp_partial.txt index 59ec8cf20b..0fda274ca0 100644 --- a/doc/src/compute_temp_partial.txt +++ b/doc/src/compute_temp_partial.txt @@ -65,8 +65,8 @@ atoms that include these constraints will be computed correctly. If needed, the subtracted degrees-of-freedom can be altered using the {extra} option of the "compute_modify"_compute_modify.html command. -See "this howto section"_Section_howto.html#howto_16 of the manual for -a discussion of different ways to compute temperature and perform +See the "Howto thermostat"_Howto_thermostat.html doc page for a +discussion of different ways to compute temperature and perform thermostatting. :line @@ -98,8 +98,8 @@ instructions on how to use the accelerated styles effectively. This compute calculates a global scalar (the temperature) and a global vector of length 6 (KE tensor), which can be accessed by indices 1-6. These values can be used by any command that uses global scalar or -vector values from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output +vector values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. The scalar value calculated by this compute is "intensive". The diff --git a/doc/src/compute_temp_profile.txt b/doc/src/compute_temp_profile.txt index 64a6abd283..8f47c8f9f4 100644 --- a/doc/src/compute_temp_profile.txt +++ b/doc/src/compute_temp_profile.txt @@ -122,8 +122,8 @@ degrees-of-freedom adjustment described in the preceding paragraph, for fixes that constrain molecular motion. It does include the adjustment due to the {extra} option, which is applied to each bin. -See "this howto section"_Section_howto.html#howto_16 of the manual for -a discussion of different ways to compute temperature and perform +See the "Howto thermostat"_Howto_thermostat.html doc page for a +discussion of different ways to compute temperature and perform thermostatting. Using this compute in conjunction with a thermostatting fix, as explained there, will effectively implement a profile-unbiased thermostat (PUT), as described in "(Evans)"_#Evans1. @@ -145,8 +145,8 @@ indices ix,iy,iz = 2,3,4 would map to row M = (iz-1)*10*10 + (iy-1)*10 indices are numbered from 1 to 10 in each dimension. These values can be used by any command that uses global scalar or -vector or array values from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output +vector or array values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. The scalar value calculated by this compute is "intensive". The diff --git a/doc/src/compute_temp_ramp.txt b/doc/src/compute_temp_ramp.txt index bc9283469c..1ae0cdfc3e 100644 --- a/doc/src/compute_temp_ramp.txt +++ b/doc/src/compute_temp_ramp.txt @@ -83,8 +83,8 @@ atoms that include these constraints will be computed correctly. If needed, the subtracted degrees-of-freedom can be altered using the {extra} option of the "compute_modify"_compute_modify.html command. -See "this howto section"_Section_howto.html#howto_16 of the manual for -a discussion of different ways to compute temperature and perform +See the "Howto thermostat"_Howto_thermostat.html doc page for a +discussion of different ways to compute temperature and perform thermostatting. [Output info:] @@ -92,8 +92,8 @@ thermostatting. This compute calculates a global scalar (the temperature) and a global vector of length 6 (KE tensor), which can be accessed by indices 1-6. These values can be used by any command that uses global scalar or -vector values from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output +vector values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. The scalar value calculated by this compute is "intensive". The diff --git a/doc/src/compute_temp_region.txt b/doc/src/compute_temp_region.txt index 3e4a80db8d..f05fa38e2c 100644 --- a/doc/src/compute_temp_region.txt +++ b/doc/src/compute_temp_region.txt @@ -81,8 +81,8 @@ If needed the number of subtracted degrees-of-freedom can be set explicitly using the {extra} option of the "compute_modify"_compute_modify.html command. -See "this howto section"_Section_howto.html#howto_16 of the manual for -a discussion of different ways to compute temperature and perform +See the "Howto thermostat"_Howto_thermostat.html doc page for a +discussion of different ways to compute temperature and perform thermostatting. [Output info:] @@ -90,8 +90,8 @@ thermostatting. This compute calculates a global scalar (the temperature) and a global vector of length 6 (KE tensor), which can be accessed by indices 1-6. These values can be used by any command that uses global scalar or -vector values from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output +vector values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. The scalar value calculated by this compute is "intensive". The diff --git a/doc/src/compute_temp_region_eff.txt b/doc/src/compute_temp_region_eff.txt index 8baf2dd46c..45c01b047f 100644 --- a/doc/src/compute_temp_region_eff.txt +++ b/doc/src/compute_temp_region_eff.txt @@ -39,8 +39,8 @@ temp/eff"_compute_temp_eff.html command. This compute calculates a global scalar (the temperature) and a global vector of length 6 (KE tensor), which can be accessed by indices 1-6. These values can be used by any command that uses global scalar or -vector values from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output +vector values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. The scalar value calculated by this compute is "intensive". The diff --git a/doc/src/compute_temp_rotate.txt b/doc/src/compute_temp_rotate.txt index 34feca7b6f..8c5679b83f 100644 --- a/doc/src/compute_temp_rotate.txt +++ b/doc/src/compute_temp_rotate.txt @@ -64,8 +64,8 @@ atoms that include these constraints will be computed correctly. If needed, the subtracted degrees-of-freedom can be altered using the {extra} option of the "compute_modify"_compute_modify.html command. -See "this howto section"_Section_howto.html#howto_16 of the manual for -a discussion of different ways to compute temperature and perform +See the "Howto thermostat"_Howto_thermostat.html doc page for a +discussion of different ways to compute temperature and perform thermostatting. [Output info:] @@ -73,8 +73,8 @@ thermostatting. This compute calculates a global scalar (the temperature) and a global vector of length 6 (KE tensor), which can be accessed by indices 1-6. These values can be used by any command that uses global scalar or -vector values from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output +vector values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. The scalar value calculated by this compute is "intensive". The diff --git a/doc/src/compute_temp_sphere.txt b/doc/src/compute_temp_sphere.txt index 9e9dff2cb6..4d4258182e 100644 --- a/doc/src/compute_temp_sphere.txt +++ b/doc/src/compute_temp_sphere.txt @@ -79,8 +79,8 @@ computed correctly. If needed, the subtracted degrees-of-freedom can be altered using the {extra} option of the "compute_modify"_compute_modify.html command. -See "this howto section"_Section_howto.html#howto_16 of the manual for -a discussion of different ways to compute temperature and perform +See the "Howto thermostat"_Howto_thermostat.html doc page for a +discussion of different ways to compute temperature and perform thermostatting. :line @@ -108,8 +108,8 @@ rotational degrees of freedom. This compute calculates a global scalar (the temperature) and a global vector of length 6 (KE tensor), which can be accessed by indices 1-6. These values can be used by any command that uses global scalar or -vector values from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output +vector values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. The scalar value calculated by this compute is "intensive". The diff --git a/doc/src/compute_ti.txt b/doc/src/compute_ti.txt index 733954d146..f5d26e1a03 100644 --- a/doc/src/compute_ti.txt +++ b/doc/src/compute_ti.txt @@ -111,9 +111,8 @@ du/dl can be found in the paper by "Eike"_#Eike. This compute calculates a global scalar, namely dUs/dlambda. This value can be used by any command that uses a global scalar value from -a compute as input. See "Section -6.15"_Section_howto.html#howto_15 for an overview of LAMMPS output -options. +a compute as input. See the "Howto output"_Howto_output.html doc page +for an overview of LAMMPS output options. The scalar value calculated by this compute is "extensive". diff --git a/doc/src/compute_torque_chunk.txt b/doc/src/compute_torque_chunk.txt index b9f832dd03..254cd0fd85 100644 --- a/doc/src/compute_torque_chunk.txt +++ b/doc/src/compute_torque_chunk.txt @@ -30,10 +30,9 @@ chunk/atom"_compute_chunk_atom.html command, which assigns each atom to a single chunk (or no chunk). The ID for this command is specified as chunkID. For example, a single chunk could be the atoms in a molecule or atoms in a spatial bin. See the "compute -chunk/atom"_compute_chunk_atom.html doc page and "Section -6.23"_Section_howto.html#howto_23 for details of how chunks can be -defined and examples of how they can be used to measure properties of -a system. +chunk/atom"_compute_chunk_atom.html and "Howto chunk"_Howto_chunk.html +doc pages for details of how chunks can be defined and examples of how +they can be used to measure properties of a system. This compute calculates the 3 components of the torque vector for eqch chunk, due to the forces on the individual atoms in the chunk around @@ -72,7 +71,7 @@ number of chunks {Nchunk} as calculated by the specified "compute chunk/atom"_compute_chunk_atom.html command. The number of columns = 3 for the 3 xyz components of the torque for each chunk. These values can be accessed by any command that uses global array values from a -compute as input. See "Section 6.15"_Section_howto.html#howto_15 +compute as input. See the "Howto output"_Howto_output.html doc page for an overview of LAMMPS output options. The array values are "intensive". The array values will be in diff --git a/doc/src/compute_vacf.txt b/doc/src/compute_vacf.txt index a0d9a3c5f7..d615f70e22 100644 --- a/doc/src/compute_vacf.txt +++ b/doc/src/compute_vacf.txt @@ -55,9 +55,8 @@ correctly with time=0 atom velocities from the restart file. This compute calculates a global vector of length 4, which can be accessed by indices 1-4 by any command that uses global vector values -from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output -options. +from a compute as input. See the "Howto output"_Howto_output.html doc +page for an overview of LAMMPS output options. The vector values are "intensive". The vector values will be in velocity^2 "units"_units.html. diff --git a/doc/src/compute_vcm_chunk.txt b/doc/src/compute_vcm_chunk.txt index de02c586bf..af1a4305d8 100644 --- a/doc/src/compute_vcm_chunk.txt +++ b/doc/src/compute_vcm_chunk.txt @@ -30,10 +30,9 @@ chunk/atom"_compute_chunk_atom.html command, which assigns each atom to a single chunk (or no chunk). The ID for this command is specified as chunkID. For example, a single chunk could be the atoms in a molecule or atoms in a spatial bin. See the "compute -chunk/atom"_compute_chunk_atom.html doc page and "Section -6.23"_Section_howto.html#howto_23 for details of how chunks can be -defined and examples of how they can be used to measure properties of -a system. +chunk/atom"_compute_chunk_atom.html and "Howto chunk"_Howto_chunk.html +doc pages for details of how chunks can be defined and examples of how +they can be used to measure properties of a system. This compute calculates the x,y,z components of the center-of-mass velocity for each chunk. This is done by summing mass*velocity for @@ -63,8 +62,8 @@ number of chunks {Nchunk} as calculated by the specified "compute chunk/atom"_compute_chunk_atom.html command. The number of columns = 3 for the x,y,z center-of-mass velocity coordinates of each chunk. These values can be accessed by any command that uses global array -values from a compute as input. See "Section -6.15"_Section_howto.html#howto_15 for an overview of LAMMPS output +values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. The array values are "intensive". The array values will be in diff --git a/doc/src/compute_voronoi_atom.txt b/doc/src/compute_voronoi_atom.txt index a280b2b151..bbd68b16ea 100644 --- a/doc/src/compute_voronoi_atom.txt +++ b/doc/src/compute_voronoi_atom.txt @@ -122,18 +122,16 @@ to locate vacancies (the coordinates are given by the atom coordinates at the time step when the compute was first invoked), while column two data can be used to identify interstitial atoms. -If the {neighbors} value is set to yes, then -this compute creates a local array with 3 columns. There -is one row for each face of each Voronoi cell. The -3 columns are the atom ID of the atom that owns the cell, -the atom ID of the atom in the neighboring cell -(or zero if the face is external), and the area of the face. -The array can be accessed by any command that -uses local values from a compute as input. See "this -section"_Section_howto.html#howto_15 for an overview of LAMMPS output -options. More specifically, the array can be accessed by a -"dump local"_dump.html command to write a file containing -all the Voronoi neighbors in a system: +If the {neighbors} value is set to yes, then this compute creates a +local array with 3 columns. There is one row for each face of each +Voronoi cell. The 3 columns are the atom ID of the atom that owns the +cell, the atom ID of the atom in the neighboring cell (or zero if the +face is external), and the area of the face. The array can be +accessed by any command that uses local values from a compute as +input. See the "Howto output"_Howto_output.html doc page for an +overview of LAMMPS output options. More specifically, the array can be +accessed by a "dump local"_dump.html command to write a file +containing all the Voronoi neighbors in a system: compute 6 all voronoi/atom neighbors yes dump d2 all local 1 dump.neighbors index c_6\[1\] c_6\[2\] c_6\[3\] :pre @@ -186,8 +184,8 @@ columns. In regular dynamic tessellation mode the first column is the Voronoi volume, the second is the neighbor count, as described above (read above for the output data in case the {occupation} keyword is specified). These values can be accessed by any command that uses -per-atom values from a compute as input. See "Section -6.15"_Section_howto.html#howto_15 for an overview of LAMMPS output +per-atom values from a compute as input. See the "Howto +output"_Howto_output.html doc page for an overview of LAMMPS output options. If the {peratom} keyword is set to "no", the per-atom array is still created, but it is not accessible. diff --git a/doc/src/compute_xrd.txt b/doc/src/compute_xrd.txt index 1a151d63f9..03fd0ecdc2 100644 --- a/doc/src/compute_xrd.txt +++ b/doc/src/compute_xrd.txt @@ -162,7 +162,7 @@ or degrees) provided with the {2Theta} values. The second column contains the computed diffraction intensities as described above. The array can be accessed by any command that uses global values from -a compute as input. See "this section"_Section_howto.html#howto_15 +a compute as input. See the "Howto output"_Howto_output.html doc page for an overview of LAMMPS output options. All array values calculated by this compute are "intensive". diff --git a/doc/src/create_box.txt b/doc/src/create_box.txt index f4ef13654c..ed05775591 100644 --- a/doc/src/create_box.txt +++ b/doc/src/create_box.txt @@ -73,9 +73,9 @@ factors that exceed these limits, you can use the "box tilt"_box.html command, with a setting of {large}; a setting of {small} is the default. -See "Section 6.12"_Section_howto.html#howto_12 of the doc pages -for a geometric description of triclinic boxes, as defined by LAMMPS, -and how to transform these parameters to and from other commonly used +See the "Howto triclinic"_Howto_triclinic.html doc page for a +geometric description of triclinic boxes, as defined by LAMMPS, and +how to transform these parameters to and from other commonly used triclinic representations. When a prism region is used, the simulation domain should normally be diff --git a/doc/src/dimension.txt b/doc/src/dimension.txt index 0531e92acf..f079f17f99 100644 --- a/doc/src/dimension.txt +++ b/doc/src/dimension.txt @@ -26,7 +26,7 @@ prior to setting up a simulation box via the "create_box"_create_box.html or "read_data"_read_data.html commands. Restart files also store this setting. -See the discussion in "Section 6"_Section_howto.html for +See the discussion on the "Howto 2d"_Howto_2d.html doc page for additional instructions on how to run 2d simulations. NOTE: Some models in LAMMPS treat particles as finite-size spheres or diff --git a/doc/src/dump.txt b/doc/src/dump.txt index ff1bf6424d..cd8bab2e65 100644 --- a/doc/src/dump.txt +++ b/doc/src/dump.txt @@ -224,12 +224,12 @@ This bounding box is convenient for many visualization programs. The meaning of the 6 character flags for "xx yy zz" is the same as above. Note that the first two numbers on each line are now xlo_bound instead -of xlo, etc, since they represent a bounding box. See "this -section"_Section_howto.html#howto_12 of the doc pages for a geometric -description of triclinic boxes, as defined by LAMMPS, simple formulas -for how the 6 bounding box extents (xlo_bound,xhi_bound,etc) are -calculated from the triclinic parameters, and how to transform those -parameters to and from other commonly used triclinic representations. +of xlo, etc, since they represent a bounding box. See the "Howto +triclinic"_Howto_triclinic.html doc page for a geometric description +of triclinic boxes, as defined by LAMMPS, simple formulas for how the +6 bounding box extents (xlo_bound,xhi_bound,etc) are calculated from +the triclinic parameters, and how to transform those parameters to and +from other commonly used triclinic representations. The "ITEM: ATOMS" line in each snapshot lists column descriptors for the per-atom lines that follow. For example, the descriptors would be @@ -530,7 +530,7 @@ so that each value is 0.0 to 1.0. If the simulation box is triclinic (tilted), then all atom coords will still be between 0.0 and 1.0. I.e. actual unscaled (x,y,z) = xs*A + ys*B + zs*C, where (A,B,C) are the non-orthogonal vectors of the simulation box edges, as discussed -in "Section 6.12"_Section_howto.html#howto_12. +on the "Howto triclinic"_Howto_triclinic.html doc page. Use {xu}, {yu}, {zu} if you want the coordinates "unwrapped" by the image flags for each atom. Unwrapped means that if the atom has diff --git a/doc/src/dump_image.txt b/doc/src/dump_image.txt index c1732be972..fcc9b25b62 100644 --- a/doc/src/dump_image.txt +++ b/doc/src/dump_image.txt @@ -356,16 +356,16 @@ is used to define body particles with internal state body style. If this keyword is not used, such particles will be drawn as spheres, the same as if they were regular atoms. -The "body"_body.html doc page describes the body styles LAMMPS -currently supports, and provides more details as to the kind of body -particles they represent and how they are drawn by this dump image -command. For all the body styles, individual atoms can be either a -body particle or a usual point (non-body) particle. Non-body +The "Howto body"_Howto_body.html doc page describes the body styles +LAMMPS currently supports, and provides more details as to the kind of +body particles they represent and how they are drawn by this dump +image command. For all the body styles, individual atoms can be +either a body particle or a usual point (non-body) particle. Non-body particles will be drawn the same way they would be as a regular atom. The {bflag1} and {bflag2} settings are numerical values which are passed to the body style to affect how the drawing of a body particle -is done. See the "body"_body.html doc page for a description of what -these parameters mean for each body style. +is done. See the "Howto body"_Howto_body.html doc page for a +description of what these parameters mean for each body style. The only setting currently allowed for the {color} value is {type}, which will color the body particles according to the atom type of the diff --git a/doc/src/fix.txt b/doc/src/fix.txt index ba2088576f..a51dc1637d 100644 --- a/doc/src/fix.txt +++ b/doc/src/fix.txt @@ -133,7 +133,7 @@ reduce"_compute_reduce.html command, or histogrammed by the "fix ave/histo"_fix_ave_histo.html command. :l :ule -See this "howto section"_Section_howto.html#howto_15 for a summary of +See the "Howto output"_Howto_output.html doc page for a summary of various LAMMPS output options, many of which involve fixes. The results of fixes that calculate global quantities can be either diff --git a/doc/src/fix_adapt.txt b/doc/src/fix_adapt.txt index 7a34f2ff44..0764d04e6d 100644 --- a/doc/src/fix_adapt.txt +++ b/doc/src/fix_adapt.txt @@ -270,10 +270,10 @@ fix 1 center adapt 10 atom diameter v_size :pre No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. -This fix is not invoked during "energy minimization"_minimize.html. +by this fix for access by various "output commands"_Howto_output.html. +No parameter of this fix can be used with the {start/stop} keywords of +the "run"_run.html command. This fix is not invoked during "energy +minimization"_minimize.html. For "rRESPA time integration"_run_style.html, this fix changes parameters on the outermost rRESPA level. diff --git a/doc/src/fix_adapt_fep.txt b/doc/src/fix_adapt_fep.txt index 5dd58bc39a..43c87a1601 100644 --- a/doc/src/fix_adapt_fep.txt +++ b/doc/src/fix_adapt_fep.txt @@ -243,10 +243,10 @@ parameters on the outermost rRESPA level. No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. -This fix is not invoked during "energy minimization"_minimize.html. +by this fix for access by various "output commands"_Howto_output.html. +No parameter of this fix can be used with the {start/stop} keywords of +the "run"_run.html command. This fix is not invoked during "energy +minimization"_minimize.html. [Restrictions:] none diff --git a/doc/src/fix_addforce.txt b/doc/src/fix_addforce.txt index 5bba9acb3f..c77cdb62af 100644 --- a/doc/src/fix_addforce.txt +++ b/doc/src/fix_addforce.txt @@ -150,11 +150,11 @@ integrator the fix is adding its forces. Default is the outermost level. This fix computes a global scalar and a global 3-vector of forces, -which can be accessed by various "output -commands"_Section_howto.html#howto_15. The scalar is the potential -energy discussed above. The vector is the total force on the group of -atoms before the forces on individual atoms are changed by the fix. -The scalar and vector values calculated by this fix are "extensive". +which can be accessed by various "output commands"_Howto_output.html. +The scalar is the potential energy discussed above. The vector is the +total force on the group of atoms before the forces on individual +atoms are changed by the fix. The scalar and vector values calculated +by this fix are "extensive". No parameter of this fix can be used with the {start/stop} keywords of the "run"_run.html command. diff --git a/doc/src/fix_addtorque.txt b/doc/src/fix_addtorque.txt index 793ec0e015..589cb37cc0 100644 --- a/doc/src/fix_addtorque.txt +++ b/doc/src/fix_addtorque.txt @@ -70,11 +70,11 @@ this fix. This allows to set at which level of the "r-RESPA"_run_style.html integrator the fix is adding its torque. Default is the outermost level. This fix computes a global scalar and a global 3-vector, which can be -accessed by various "output commands"_Section_howto.html#howto_15. -The scalar is the potential energy discussed above. The vector is the -total torque on the group of atoms before the forces on individual -atoms are changed by the fix. The scalar and vector values calculated -by this fix are "extensive". +accessed by various "output commands"_Howto_output.html. The scalar +is the potential energy discussed above. The vector is the total +torque on the group of atoms before the forces on individual atoms are +changed by the fix. The scalar and vector values calculated by this +fix are "extensive". No parameter of this fix can be used with the {start/stop} keywords of the "run"_run.html command. diff --git a/doc/src/fix_append_atoms.txt b/doc/src/fix_append_atoms.txt index 27070c9be5..ba7b4a3e74 100644 --- a/doc/src/fix_append_atoms.txt +++ b/doc/src/fix_append_atoms.txt @@ -87,10 +87,10 @@ define the lattice spacings. No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. -This fix is not invoked during "energy minimization"_minimize.html. +by this fix for access by various "output commands"_Howto_output.html. +No parameter of this fix can be used with the {start/stop} keywords of +the "run"_run.html command. This fix is not invoked during "energy +minimization"_minimize.html. [Restrictions:] diff --git a/doc/src/fix_atc.txt b/doc/src/fix_atc.txt index 49014f0591..af3270ff52 100644 --- a/doc/src/fix_atc.txt +++ b/doc/src/fix_atc.txt @@ -102,7 +102,13 @@ Note coupling and post-processing can be combined in the same simulations using [Restart, fix_modify, output, run start/stop, minimize info:] -No information about this fix is written to "binary restart files"_restart.html. The "fix_modify"_fix_modify.html options relevant to this fix are listed below. No global scalar or vector or per-atom quantities are stored by this fix for access by various "output commands"_Section_howto.html#howto_15. No parameter of this fix can be used with the {start/stop} keywords of the "run"_run.html command. This fix is not invoked during "energy minimization"_minimize.html. +No information about this fix is written to "binary restart +files"_restart.html. The "fix_modify"_fix_modify.html options +relevant to this fix are listed below. No global scalar or vector or +per-atom quantities are stored by this fix for access by various +"output commands"_Howto_output.html. No parameter of this fix can be +used with the {start/stop} keywords of the "run"_run.html command. +This fix is not invoked during "energy minimization"_minimize.html. [Restrictions:] diff --git a/doc/src/fix_atom_swap.txt b/doc/src/fix_atom_swap.txt index bf56277214..0b3be3ce5e 100644 --- a/doc/src/fix_atom_swap.txt +++ b/doc/src/fix_atom_swap.txt @@ -150,8 +150,8 @@ None of the "fix_modify"_fix_modify.html options are relevant to this fix. This fix computes a global vector of length 2, which can be accessed -by various "output commands"_Section_howto.html#howto_15. The vector -values are the following global cumulative quantities: +by various "output commands"_Howto_output.html. The vector values are +the following global cumulative quantities: 1 = swap attempts 2 = swap successes :ul diff --git a/doc/src/fix_ave_atom.txt b/doc/src/fix_ave_atom.txt index 23e4ed235b..05bd0f6fa7 100644 --- a/doc/src/fix_ave_atom.txt +++ b/doc/src/fix_ave_atom.txt @@ -38,7 +38,7 @@ fix 1 all ave/atom 10 20 1000 c_my_stress\[*\] :pre Use one or more per-atom vectors as inputs every few timesteps, and average them atom by atom over longer timescales. The resulting per-atom averages can be used by other "output -commands"_Section_howto.html#howto_15 such as the "fix +commands"_Howto_output.html such as the "fix ave/chunk"_fix_ave_chunk.html or "dump custom"_dump.html commands. The group specified with the command means only atoms within the group @@ -155,14 +155,14 @@ No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global scalar or vector quantities are stored by this fix for access by various "output -commands"_Section_howto.html#howto_15. +commands"_Howto_output.html. This fix produces a per-atom vector or array which can be accessed by -various "output commands"_Section_howto.html#howto_15. A vector is -produced if only a single quantity is averaged by this fix. If two or -more quantities are averaged, then an array of values is produced. -The per-atom values can only be accessed on timesteps that are -multiples of {Nfreq} since that is when averaging is performed. +various "output commands"_Howto_output.html. A vector is produced if +only a single quantity is averaged by this fix. If two or more +quantities are averaged, then an array of values is produced. The +per-atom values can only be accessed on timesteps that are multiples +of {Nfreq} since that is when averaging is performed. No parameter of this fix can be used with the {start/stop} keywords of the "run"_run.html command. This fix is not invoked during "energy diff --git a/doc/src/fix_ave_chunk.txt b/doc/src/fix_ave_chunk.txt index 8e2a09e33f..e9d0ef7e72 100644 --- a/doc/src/fix_ave_chunk.txt +++ b/doc/src/fix_ave_chunk.txt @@ -85,17 +85,17 @@ fix 1 flow ave/chunk 100 10 1000 cc1 vx vz norm sample file vel.profile :pre Use one or more per-atom vectors as inputs every few timesteps, sum the values over the atoms in each chunk at each timestep, then average the per-chunk values over longer timescales. The resulting chunk -averages can be used by other "output -commands"_Section_howto.html#howto_15 such as "thermo_style -custom"_thermo_style.html, and can also be written to a file. +averages can be used by other "output commands"_Howto_output.html such +as "thermo_style custom"_thermo_style.html, and can also be written to +a file. In LAMMPS, chunks are collections of atoms defined by a "compute chunk/atom"_compute_chunk_atom.html command, which assigns each atom to a single chunk (or no chunk). The ID for this command is specified as chunkID. For example, a single chunk could be the atoms in a molecule or atoms in a spatial bin. See the "compute -chunk/atom"_compute_chunk_atom.html doc page and "Section -6.23"_Section_howto.html#howto_23 for details of how chunks can be +chunk/atom"_compute_chunk_atom.html doc page and the "Howto +chunk"_Howto_chunk.html doc page for details of how chunks can be defined and examples of how they can be used to measure properties of a system. @@ -456,20 +456,19 @@ files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. This fix computes a global array of values which can be accessed by -various "output commands"_Section_howto.html#howto_15. The values can -only be accessed on timesteps that are multiples of {Nfreq} since that -is when averaging is performed. The global array has # of rows = -the number of chunks {Nchunk} as calculated by the specified "compute +various "output commands"_Howto_output.html. The values can only be +accessed on timesteps that are multiples of {Nfreq} since that is when +averaging is performed. The global array has # of rows = the number +of chunks {Nchunk} as calculated by the specified "compute chunk/atom"_compute_chunk_atom.html command. The # of columns = M+1+Nvalues, where M = 1 to 4, depending on whether the optional -columns for OrigID and CoordN are used, as explained above. -Following the optional columns, the next column contains the count of -atoms in the chunk, and the remaining columns are the Nvalue -quantities. When the array is accessed with a row I that exceeds the -current number of chunks, than a 0.0 is returned by the fix instead of -an error, since the number of chunks can vary as a simulation runs -depending on how that value is computed by the compute chunk/atom -command. +columns for OrigID and CoordN are used, as explained above. Following +the optional columns, the next column contains the count of atoms in +the chunk, and the remaining columns are the Nvalue quantities. When +the array is accessed with a row I that exceeds the current number of +chunks, than a 0.0 is returned by the fix instead of an error, since +the number of chunks can vary as a simulation runs depending on how +that value is computed by the compute chunk/atom command. The array values calculated by this fix are treated as "intensive", since they are typically already normalized by the count of atoms in diff --git a/doc/src/fix_ave_correlate.txt b/doc/src/fix_ave_correlate.txt index 98f352cb74..74ce3f340e 100644 --- a/doc/src/fix_ave_correlate.txt +++ b/doc/src/fix_ave_correlate.txt @@ -68,7 +68,7 @@ calculate time correlations between them at varying time intervals, and average the correlation data over longer timescales. The resulting correlation values can be time integrated by "variables"_variable.html or used by other "output -commands"_Section_howto.html#howto_15 such as "thermo_style +commands"_Howto_output.html such as "thermo_style custom"_thermo_style.html, and can also be written to a file. See the "fix ave/correlate/long"_fix_ave_correlate_long.html command for an alternate method for computing correlation functions efficiently over @@ -313,16 +313,15 @@ files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. This fix computes a global array of values which can be accessed by -various "output commands"_Section_howto.html#howto_15. The values can -only be accessed on timesteps that are multiples of {Nfreq} since that -is when averaging is performed. The global array has # of rows = -{Nrepeat} and # of columns = Npair+2. The first column has the time -delta (in timesteps) between the pairs of input values used to -calculate the correlation, as described above. The 2nd column has the -number of samples contributing to the correlation average, as -described above. The remaining Npair columns are for I,J pairs of the -N input values, as determined by the {type} keyword, as described -above. +various "output commands"_Howto_output.html. The values can only be +accessed on timesteps that are multiples of {Nfreq} since that is when +averaging is performed. The global array has # of rows = {Nrepeat} +and # of columns = Npair+2. The first column has the time delta (in +timesteps) between the pairs of input values used to calculate the +correlation, as described above. The 2nd column has the number of +samples contributing to the correlation average, as described above. +The remaining Npair columns are for I,J pairs of the N input values, +as determined by the {type} keyword, as described above. For {type} = {auto}, the Npair = N columns are ordered: C11, C22, ..., CNN. :ulb,l diff --git a/doc/src/fix_ave_histo.txt b/doc/src/fix_ave_histo.txt index 5155f42e7b..e2fd2e04e8 100644 --- a/doc/src/fix_ave_histo.txt +++ b/doc/src/fix_ave_histo.txt @@ -69,10 +69,9 @@ fix 1 all ave/histo/weight 1 1 1 10 100 2000 c_XRD\[1\] c_XRD\[2\] :pre Use one or more values as inputs every few timesteps to create a single histogram. The histogram can then be averaged over longer timescales. The resulting histogram can be used by other "output -commands"_Section_howto.html#howto_15, and can also be written to a -file. The fix ave/histo/weight command has identical syntax to fix -ave/histo, except that exactly two values must be specified. See -details below. +commands"_Howto_output.html, and can also be written to a file. The +fix ave/histo/weight command has identical syntax to fix ave/histo, +except that exactly two values must be specified. See details below. The group specified with this command is ignored for global and local input values. For per-atom input values, only atoms in the group @@ -320,10 +319,10 @@ files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. This fix produces a global vector and global array which can be -accessed by various "output commands"_Section_howto.html#howto_15. -The values can only be accessed on timesteps that are multiples of -{Nfreq} since that is when a histogram is generated. The global -vector has 4 values: +accessed by various "output commands"_Howto_output.html. The values +can only be accessed on timesteps that are multiples of {Nfreq} since +that is when a histogram is generated. The global vector has 4 +values: 1 = total counts in the histogram 2 = values that were not histogrammed (see {beyond} keyword) diff --git a/doc/src/fix_ave_time.txt b/doc/src/fix_ave_time.txt index b61f56cf02..e973a36360 100644 --- a/doc/src/fix_ave_time.txt +++ b/doc/src/fix_ave_time.txt @@ -64,7 +64,7 @@ fix 1 all ave/time 1 100 1000 f_indent f_indent\[1\] file temp.indent off 1 :pre Use one or more global values as inputs every few timesteps, and average them over longer timescales. The resulting averages can be -used by other "output commands"_Section_howto.html#howto_15 such as +used by other "output commands"_Howto_output.html such as "thermo_style custom"_thermo_style.html, and can also be written to a file. Note that if no time averaging is done, this command can be used as a convenient way to simply output one or more global values to @@ -305,10 +305,9 @@ files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. This fix produces a global scalar or global vector or global array -which can be accessed by various "output -commands"_Section_howto.html#howto_15. The values can only be -accessed on timesteps that are multiples of {Nfreq} since that is when -averaging is performed. +which can be accessed by various "output commands"_Howto_output.html. +The values can only be accessed on timesteps that are multiples of +{Nfreq} since that is when averaging is performed. A scalar is produced if only a single input value is averaged and {mode} = scalar. A vector is produced if multiple input values are diff --git a/doc/src/fix_aveforce.txt b/doc/src/fix_aveforce.txt index 4944996695..3497b33ef4 100644 --- a/doc/src/fix_aveforce.txt +++ b/doc/src/fix_aveforce.txt @@ -95,10 +95,10 @@ fix. This allows to set at which level of the "r-RESPA"_run_style.html integrator the fix is adding its forces. Default is the outermost level. This fix computes a global 3-vector of forces, which can be accessed -by various "output commands"_Section_howto.html#howto_15. This is the -total force on the group of atoms before the forces on individual -atoms are changed by the fix. The vector values calculated by this -fix are "extensive". +by various "output commands"_Howto_output.html. This is the total +force on the group of atoms before the forces on individual atoms are +changed by the fix. The vector values calculated by this fix are +"extensive". No parameter of this fix can be used with the {start/stop} keywords of the "run"_run.html command. diff --git a/doc/src/fix_balance.txt b/doc/src/fix_balance.txt index f148e6f996..b98fd85c3b 100644 --- a/doc/src/fix_balance.txt +++ b/doc/src/fix_balance.txt @@ -357,8 +357,8 @@ number of particles (or total weight) on any processor to the average number of particles (or total weight) per processor. These quantities can be accessed by various "output -commands"_Section_howto.html#howto_15. The scalar and vector values -calculated by this fix are "intensive". +commands"_Howto_output.html. The scalar and vector values calculated +by this fix are "intensive". No parameter of this fix can be used with the {start/stop} keywords of the "run"_run.html command. This fix is not invoked during "energy diff --git a/doc/src/fix_bond_break.txt b/doc/src/fix_bond_break.txt index 83364b9efb..b43053c461 100644 --- a/doc/src/fix_bond_break.txt +++ b/doc/src/fix_bond_break.txt @@ -116,8 +116,8 @@ are relevant to this fix. This fix computes two statistics which it stores in a global vector of length 2, which can be accessed by various "output -commands"_Section_howto.html#howto_15. The vector values calculated -by this fix are "intensive". +commands"_Howto_output.html. The vector values calculated by this fix +are "intensive". These are the 2 quantities: diff --git a/doc/src/fix_bond_create.txt b/doc/src/fix_bond_create.txt index c0045ac0f0..a55ba1ff6e 100644 --- a/doc/src/fix_bond_create.txt +++ b/doc/src/fix_bond_create.txt @@ -211,8 +211,8 @@ are relevant to this fix. This fix computes two statistics which it stores in a global vector of length 2, which can be accessed by various "output -commands"_Section_howto.html#howto_15. The vector values calculated -by this fix are "intensive". +commands"_Howto_output.html. The vector values calculated by this fix +are "intensive". These are the 2 quantities: diff --git a/doc/src/fix_bond_react.txt b/doc/src/fix_bond_react.txt index f85ef9bc1a..006f59100f 100644 --- a/doc/src/fix_bond_react.txt +++ b/doc/src/fix_bond_react.txt @@ -298,9 +298,8 @@ relevant to this fix. This fix computes one statistic for each {react} argument that it stores in a global vector, of length 'number of react arguments', that -can be accessed by various "output -commands"_Section_howto.html#howto_15. The vector values calculated by -this fix are "intensive". +can be accessed by various "output commands"_Howto_output.html. The +vector values calculated by this fix are "intensive". These is 1 quantity for each react argument: diff --git a/doc/src/fix_bond_swap.txt b/doc/src/fix_bond_swap.txt index ca7069e247..8d5df7e4e0 100644 --- a/doc/src/fix_bond_swap.txt +++ b/doc/src/fix_bond_swap.txt @@ -150,13 +150,13 @@ the Boltzmann criterion. This fix computes two statistical quantities as a global 2-vector of output, which can be accessed by various "output -commands"_Section_howto.html#howto_15. The first component of the -vector is the cumulative number of swaps performed by all processors. -The second component of the vector is the cumulative number of swaps -attempted (whether accepted or rejected). Note that a swap "attempt" -only occurs when swap partners meeting the criteria described above -are found on a particular timestep. The vector values calculated by -this fix are "intensive". +commands"_Howto_output.html. The first component of the vector is the +cumulative number of swaps performed by all processors. The second +component of the vector is the cumulative number of swaps attempted +(whether accepted or rejected). Note that a swap "attempt" only +occurs when swap partners meeting the criteria described above are +found on a particular timestep. The vector values calculated by this +fix are "intensive". No parameter of this fix can be used with the {start/stop} keywords of the "run"_run.html command. This fix is not invoked during "energy diff --git a/doc/src/fix_box_relax.txt b/doc/src/fix_box_relax.txt index e3d75ee858..a625f0c5b8 100644 --- a/doc/src/fix_box_relax.txt +++ b/doc/src/fix_box_relax.txt @@ -315,17 +315,15 @@ specified by the {press} keyword will be unaffected by the {temp} setting. This fix computes a global scalar which can be accessed by various -"output commands"_Section_howto.html#howto_15. The scalar is the -pressure-volume energy, plus the strain energy, if it exists, -as described above. -The energy values reported at the -end of a minimization run under "Minimization stats" include this -energy, and so differ from what LAMMPS normally reports as potential -energy. This fix does not support the "fix_modify"_fix_modify.html -{energy} option, because that would result in double-counting of the -fix energy in the minimization energy. Instead, the fix energy can be -explicitly added to the potential energy using one of these two -variants: +"output commands"_Howto_output.html. The scalar is the pressure-volume +energy, plus the strain energy, if it exists, as described above. The +energy values reported at the end of a minimization run under +"Minimization stats" include this energy, and so differ from what +LAMMPS normally reports as potential energy. This fix does not support +the "fix_modify"_fix_modify.html {energy} option, because that would +result in double-counting of the fix energy in the minimization +energy. Instead, the fix energy can be explicitly added to the +potential energy using one of these two variants: variable emin equal pe+f_1 :pre diff --git a/doc/src/fix_cmap.txt b/doc/src/fix_cmap.txt index f8de2b4efe..d352f0e652 100644 --- a/doc/src/fix_cmap.txt +++ b/doc/src/fix_cmap.txt @@ -103,9 +103,9 @@ the system's virial as part of "thermodynamic output"_thermo_style.html. The default is {virial yes} This fix computes a global scalar which can be accessed by various -"output commands"_Section_howto.html#howto_15. The scalar is the -potential energy discussed above. The scalar value calculated by this -fix is "extensive". +"output commands"_Howto_output.html. The scalar is the potential +energy discussed above. The scalar value calculated by this fix is +"extensive". No parameter of this fix can be used with the {start/stop} keywords of the "run"_run.html command. diff --git a/doc/src/fix_colvars.txt b/doc/src/fix_colvars.txt index e48dedacd9..2d3000e6ea 100644 --- a/doc/src/fix_colvars.txt +++ b/doc/src/fix_colvars.txt @@ -99,9 +99,9 @@ to the system's potential energy as part of "thermodynamic output"_thermo_style.html. This fix computes a global scalar which can be accessed by various -"output commands"_Section_howto.html#howto_15. The scalar is the -cumulative energy change due to this fix. The scalar value -calculated by this fix is "extensive". +"output commands"_Howto_output.html. The scalar is the cumulative +energy change due to this fix. The scalar value calculated by this +fix is "extensive". [Restrictions:] diff --git a/doc/src/fix_controller.txt b/doc/src/fix_controller.txt index b8d2cb43be..710642c0ea 100644 --- a/doc/src/fix_controller.txt +++ b/doc/src/fix_controller.txt @@ -180,9 +180,9 @@ files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. This fix produces a global vector with 3 values which can be accessed -by various "output commands"_Section_howto.html#howto_15. The values -can be accessed on any timestep, though they are only updated on -timesteps that are a multiple of {Nevery}. +by various "output commands"_Howto_output.html. The values can be +accessed on any timestep, though they are only updated on timesteps +that are a multiple of {Nevery}. The three values are the most recent updates made to the control variable by each of the 3 terms in the PID equation above. The first diff --git a/doc/src/fix_deform.txt b/doc/src/fix_deform.txt index 681986561a..09261e2423 100644 --- a/doc/src/fix_deform.txt +++ b/doc/src/fix_deform.txt @@ -572,10 +572,9 @@ instructions on how to use the accelerated styles effectively. This fix will restore the initial box settings from "binary restart files"_restart.html, which allows the fix to be properly continue deformation, when using the start/stop options of the "run"_run.html -command. None of the "fix_modify"_fix_modify.html options -are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. +command. None of the "fix_modify"_fix_modify.html options are +relevant to this fix. No global or per-atom quantities are stored by +this fix for access by various "output commands"_Howto_output.html. This fix can perform deformation over multiple runs, using the {start} and {stop} keywords of the "run"_run.html command. See the diff --git a/doc/src/fix_deposit.txt b/doc/src/fix_deposit.txt index 477c14ea89..285e720555 100644 --- a/doc/src/fix_deposit.txt +++ b/doc/src/fix_deposit.txt @@ -116,8 +116,8 @@ side = {in}. NOTE: LAMMPS checks that the specified region is wholly inside the simulation box. It can do this correctly for orthonormal simulation -boxes. However for "triclinic boxes"_Section_howto.html#howto_12, it -only tests against the larger orthonormal box that bounds the tilted +boxes. However for "triclinic boxes"_Howto_triclinic.html, it only +tests against the larger orthonormal box that bounds the tilted simulation box. If the specified region includes volume outside the tilted box, then an insertion will likely fail, leading to a "lost atoms" error. Thus for triclinic boxes you should insure the @@ -263,9 +263,9 @@ operation of the fix continues in an uninterrupted fashion. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored by this fix for -access by various "output commands"_Section_howto.html#howto_15. No -parameter of this fix can be used with the {start/stop} keywords of -the "run"_run.html command. This fix is not invoked during "energy +access by various "output commands"_Howto_output.html. No parameter +of this fix can be used with the {start/stop} keywords of the +"run"_run.html command. This fix is not invoked during "energy minimization"_minimize.html. [Restrictions:] diff --git a/doc/src/fix_dpd_source.txt b/doc/src/fix_dpd_source.txt index b6decc657c..bbfc99e8c8 100644 --- a/doc/src/fix_dpd_source.txt +++ b/doc/src/fix_dpd_source.txt @@ -63,10 +63,10 @@ cuboid domain to apply the source flux to. No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. -This fix is not invoked during "energy minimization"_minimize.html. +by this fix for access by various "output commands"_Howto_output.html. +No parameter of this fix can be used with the {start/stop} keywords of +the "run"_run.html command. This fix is not invoked during "energy +minimization"_minimize.html. [Restrictions:] diff --git a/doc/src/fix_drag.txt b/doc/src/fix_drag.txt index 235d3d38b5..a67ec6aaf2 100644 --- a/doc/src/fix_drag.txt +++ b/doc/src/fix_drag.txt @@ -47,9 +47,9 @@ fix. This allows to set at which level of the "r-RESPA"_run_style.html integrator the fix is adding its forces. Default is the outermost level. This fix computes a global 3-vector of forces, which can be accessed -by various "output commands"_Section_howto.html#howto_15. This is the -total force on the group of atoms by the drag force. The vector -values calculated by this fix are "extensive". +by various "output commands"_Howto_output.html. This is the total +force on the group of atoms by the drag force. The vector values +calculated by this fix are "extensive". No parameter of this fix can be used with the {start/stop} keywords of the "run"_run.html command. This fix is not invoked during "energy diff --git a/doc/src/fix_drude.txt b/doc/src/fix_drude.txt index faa354b314..4a3d30a9ca 100644 --- a/doc/src/fix_drude.txt +++ b/doc/src/fix_drude.txt @@ -25,10 +25,10 @@ fix 1 all drude C C N C N D D D :pre [Description:] Assign each atom type in the system to be one of 3 kinds of atoms -within the Drude polarization model. This fix is designed to be -used with the "thermalized Drude oscillator -model"_tutorial_drude.html. Polarizable models in LAMMPS -are described in "this Section"_Section_howto.html#howto_25. +within the Drude polarization model. This fix is designed to be used +with the "thermalized Drude oscillator model"_Howto_drude.html. +Polarizable models in LAMMPS are described on the "Howto +polarizable"_Howto_polarizable.html doc page. The three possible types can be designated with an integer (0,1,2) or capital letter (N,C,D): diff --git a/doc/src/fix_drude_transform.txt b/doc/src/fix_drude_transform.txt index 2e094d528c..54cdfa956e 100644 --- a/doc/src/fix_drude_transform.txt +++ b/doc/src/fix_drude_transform.txt @@ -34,8 +34,8 @@ Transform the coordinates of Drude oscillators from real to reduced and back for thermalizing the Drude oscillators as described in "(Lamoureux)"_#Lamoureux1 using a Nose-Hoover thermostat. This fix is designed to be used with the "thermalized Drude oscillator -model"_tutorial_drude.html. Polarizable models in LAMMPS are -described in "this Section"_Section_howto.html#howto_25. +model"_Howto_drude.html. Polarizable models in LAMMPS are described +on the "Howto polarizable"_Howto_polarizable.html doc page. Drude oscillators are a pair of atoms representing a single polarizable atom. Ideally, the mass of Drude particles would vanish diff --git a/doc/src/fix_dt_reset.txt b/doc/src/fix_dt_reset.txt index 7605395ca0..428128feda 100644 --- a/doc/src/fix_dt_reset.txt +++ b/doc/src/fix_dt_reset.txt @@ -82,8 +82,8 @@ files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. This fix computes a global scalar which can be accessed by various -"output commands"_Section_howto.html#howto_15. The scalar stores -the last timestep on which the timestep was reset to a new value. +"output commands"_Howto_output.html. The scalar stores the last +timestep on which the timestep was reset to a new value. The scalar value calculated by this fix is "intensive". diff --git a/doc/src/fix_efield.txt b/doc/src/fix_efield.txt index 5d2b86fe4b..a248a03b07 100644 --- a/doc/src/fix_efield.txt +++ b/doc/src/fix_efield.txt @@ -134,11 +134,10 @@ fix. This allows to set at which level of the "r-RESPA"_run_style.html integrator the fix adding its forces. Default is the outermost level. This fix computes a global scalar and a global 3-vector of forces, -which can be accessed by various "output -commands"_Section_howto.html#howto_15. The scalar is the potential -energy discussed above. The vector is the total force added to the -group of atoms. The scalar and vector values calculated by this fix -are "extensive". +which can be accessed by various "output commands"_Howto_output.html. +The scalar is the potential energy discussed above. The vector is the +total force added to the group of atoms. The scalar and vector values +calculated by this fix are "extensive". No parameter of this fix can be used with the {start/stop} keywords of the "run"_run.html command. diff --git a/doc/src/fix_enforce2d.txt b/doc/src/fix_enforce2d.txt index 67b351e4b8..b0d8c691b5 100644 --- a/doc/src/fix_enforce2d.txt +++ b/doc/src/fix_enforce2d.txt @@ -55,9 +55,9 @@ instructions on how to use the accelerated styles effectively. No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. +by this fix for access by various "output commands"_Howto_output.html. +No parameter of this fix can be used with the {start/stop} keywords of +the "run"_run.html command. The forces due to this fix are imposed during an energy minimization, invoked by the "minimize"_minimize.html command. diff --git a/doc/src/fix_evaporate.txt b/doc/src/fix_evaporate.txt index ed6c6d0377..be8b351986 100644 --- a/doc/src/fix_evaporate.txt +++ b/doc/src/fix_evaporate.txt @@ -73,9 +73,9 @@ files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. This fix computes a global scalar, which can be accessed by various -"output commands"_Section_howto.html#howto_15. The scalar is the -cumulative number of deleted atoms. The scalar value calculated by -this fix is "intensive". +"output commands"_Howto_output.html. The scalar is the cumulative +number of deleted atoms. The scalar value calculated by this fix is +"intensive". No parameter of this fix can be used with the {start/stop} keywords of the "run"_run.html command. This fix is not invoked during "energy diff --git a/doc/src/fix_external.txt b/doc/src/fix_external.txt index 30e34b4858..bf80b1b231 100644 --- a/doc/src/fix_external.txt +++ b/doc/src/fix_external.txt @@ -31,10 +31,10 @@ fix 1 all external pf/array 10 :pre [Description:] This fix allows external programs that are running LAMMPS through its -"library interface"_Section_howto.html#howto_19 to modify certain -LAMMPS properties on specific timesteps, similar to the way other -fixes do. The external driver can be a "C/C++ or Fortran -program"_Section_howto.html#howto_19 or a "Python script"_Python.html. +"library interface"_Howto_library.html to modify certain LAMMPS +properties on specific timesteps, similar to the way other fixes do. +The external driver can be a "C/C++ or Fortran +program"_Howto_library.html or a "Python script"_Python.html. :line @@ -136,9 +136,8 @@ external program to the system's virial as part of "thermodynamic output"_thermo_style.html. The default is {virial yes} This fix computes a global scalar which can be accessed by various -"output commands"_Section_howto.html#howto_15. The scalar is the -potential energy discussed above. The scalar stored by this fix -is "extensive". +"output commands"_Howto_output.html. The scalar is the potential +energy discussed above. The scalar stored by this fix is "extensive". No parameter of this fix can be used with the {start/stop} keywords of the "run"_run.html command. diff --git a/doc/src/fix_filter_corotate.txt b/doc/src/fix_filter_corotate.txt index b782d285c7..a75a3b7b44 100644 --- a/doc/src/fix_filter_corotate.txt +++ b/doc/src/fix_filter_corotate.txt @@ -63,10 +63,9 @@ No information about these fixes is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to these fixes. No global or per-atom quantities are stored by these fixes for access by various "output -commands"_Section_howto.html#howto_15. No parameter of these fixes -can be used with the {start/stop} keywords of the "run"_run.html -command. These fixes are not invoked during "energy -minimization"_minimize.html. +commands"_Howto_output.html. No parameter of these fixes can be used +with the {start/stop} keywords of the "run"_run.html command. These +fixes are not invoked during "energy minimization"_minimize.html. [Restrictions:] diff --git a/doc/src/fix_flow_gauss.txt b/doc/src/fix_flow_gauss.txt index efa58ea65f..0980076062 100644 --- a/doc/src/fix_flow_gauss.txt +++ b/doc/src/fix_flow_gauss.txt @@ -128,11 +128,11 @@ integrator the fix computes and adds the external acceleration. Default is the outermost level. This fix computes a global scalar and a global 3-vector of forces, -which can be accessed by various "output -commands"_Section_howto.html#howto_15. The scalar is the negative of the -work done on the system, see above discussion. The vector is the total force -that this fix applied to the group of atoms on the current timestep. -The scalar and vector values calculated by this fix are "extensive". +which can be accessed by various "output commands"_Howto_output.html. +The scalar is the negative of the work done on the system, see above +discussion. The vector is the total force that this fix applied to +the group of atoms on the current timestep. The scalar and vector +values calculated by this fix are "extensive". No parameter of this fix can be used with the {start/stop} keywords of the "run"_run.html command. diff --git a/doc/src/fix_freeze.txt b/doc/src/fix_freeze.txt index 9619f4120b..43714df802 100644 --- a/doc/src/fix_freeze.txt +++ b/doc/src/fix_freeze.txt @@ -60,10 +60,10 @@ files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. This fix computes a global 3-vector of forces, which can be accessed -by various "output commands"_Section_howto.html#howto_15. This is the -total force on the group of atoms before the forces on individual -atoms are changed by the fix. The vector values calculated by this -fix are "extensive". +by various "output commands"_Howto_output.html. This is the total +force on the group of atoms before the forces on individual atoms are +changed by the fix. The vector values calculated by this fix are +"extensive". No parameter of this fix can be used with the {start/stop} keywords of the "run"_run.html command. This fix is not invoked during "energy diff --git a/doc/src/fix_gcmc.txt b/doc/src/fix_gcmc.txt index 191bc32b14..9630d856be 100644 --- a/doc/src/fix_gcmc.txt +++ b/doc/src/fix_gcmc.txt @@ -382,8 +382,8 @@ None of the "fix_modify"_fix_modify.html options are relevant to this fix. This fix computes a global vector of length 8, which can be accessed -by various "output commands"_Section_howto.html#howto_15. The vector -values are the following global cumulative quantities: +by various "output commands"_Howto_output.html. The vector values are +the following global cumulative quantities: 1 = translation attempts 2 = translation successes diff --git a/doc/src/fix_gld.txt b/doc/src/fix_gld.txt index 1425f62e13..06ac5d68cb 100644 --- a/doc/src/fix_gld.txt +++ b/doc/src/fix_gld.txt @@ -126,7 +126,7 @@ sense, a restarted simulation should produce the same behavior. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored by this fix for -access by various "output commands"_Section_howto.html#howto_15. +access by various "output commands"_Howto_output.html. This fix can ramp its target temperature over multiple runs, using the {start} and {stop} keywords of the "run"_run.html command. See the diff --git a/doc/src/fix_gle.txt b/doc/src/fix_gle.txt index 6568060f0c..d91dd8dee9 100644 --- a/doc/src/fix_gle.txt +++ b/doc/src/fix_gle.txt @@ -116,9 +116,9 @@ system's potential energy as part of "thermodynamic output"_thermo_style.html. This fix computes a global scalar which can be accessed by various -"output commands"_Section_howto.html#howto_15. The scalar is the -cumulative energy change due to this fix. The scalar value -calculated by this fix is "extensive". +"output commands"_Howto_output.html. The scalar is the cumulative +energy change due to this fix. The scalar value calculated by this +fix is "extensive". [Restrictions:] diff --git a/doc/src/fix_gravity.txt b/doc/src/fix_gravity.txt index f39955d4f8..786f145608 100644 --- a/doc/src/fix_gravity.txt +++ b/doc/src/fix_gravity.txt @@ -124,11 +124,11 @@ fix. This allows to set at which level of the "r-RESPA"_run_style.html integrator the fix is adding its forces. Default is the outermost level. This fix computes a global scalar which can be accessed by various -"output commands"_Section_howto.html#howto_15. This scalar is the -gravitational potential energy of the particles in the defined field, -namely mass * (g dot x) for each particles, where x and mass are the -particles position and mass, and g is the gravitational field. The -scalar value calculated by this fix is "extensive". +"output commands"_Howto_output.html. This scalar is the gravitational +potential energy of the particles in the defined field, namely mass * +(g dot x) for each particles, where x and mass are the particles +position and mass, and g is the gravitational field. The scalar value +calculated by this fix is "extensive". No parameter of this fix can be used with the {start/stop} keywords of the "run"_run.html command. This fix is not invoked during "energy diff --git a/doc/src/fix_halt.txt b/doc/src/fix_halt.txt index 08043eb5fb..55f313e40f 100644 --- a/doc/src/fix_halt.txt +++ b/doc/src/fix_halt.txt @@ -133,10 +133,10 @@ files. No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. -This fix is not invoked during "energy minimization"_minimize.html. +by this fix for access by various "output commands"_Howto_output.html. +No parameter of this fix can be used with the {start/stop} keywords of +the "run"_run.html command. This fix is not invoked during "energy +minimization"_minimize.html. [Restrictions:] none diff --git a/doc/src/fix_heat.txt b/doc/src/fix_heat.txt index 23db87dac2..a0e9b945fc 100644 --- a/doc/src/fix_heat.txt +++ b/doc/src/fix_heat.txt @@ -108,12 +108,11 @@ files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. This fix computes a global scalar which can be accessed by various -"output commands"_Section_howto.html#howto_15. This scalar is the -most recent value by which velocites were scaled. The scalar value -calculated by this fix is "intensive". If {eflux} is specified as -an atom-style variable, this fix computes the average value by which -the velocities were scaled for all of the atoms that had their -velocities scaled. +"output commands"_Howto_output.html. This scalar is the most recent +value by which velocites were scaled. The scalar value calculated by +this fix is "intensive". If {eflux} is specified as an atom-style +variable, this fix computes the average value by which the velocities +were scaled for all of the atoms that had their velocities scaled. No parameter of this fix can be used with the {start/stop} keywords of the "run"_run.html command. This fix is not invoked during "energy diff --git a/doc/src/fix_imd.txt b/doc/src/fix_imd.txt index b275612819..1a1f11c2cf 100644 --- a/doc/src/fix_imd.txt +++ b/doc/src/fix_imd.txt @@ -136,9 +136,9 @@ No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global scalar or vector or per-atom quantities are stored by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. -This fix is not invoked during "energy minimization"_minimize.html. +commands"_Howto_output.html. No parameter of this fix can be used +with the {start/stop} keywords of the "run"_run.html command. This +fix is not invoked during "energy minimization"_minimize.html. [Restrictions:] diff --git a/doc/src/fix_indent.txt b/doc/src/fix_indent.txt index c9a791ae4e..1f67c0b242 100644 --- a/doc/src/fix_indent.txt +++ b/doc/src/fix_indent.txt @@ -180,8 +180,8 @@ integrator the fix is adding its forces. Default is the outermost level. This fix computes a global scalar energy and a global 3-vector of forces (on the indenter), which can be accessed by various "output -commands"_Section_howto.html#howto_15. The scalar and vector values -calculated by this fix are "extensive". +commands"_Howto_output.html. The scalar and vector values calculated +by this fix are "extensive". The forces due to this fix are imposed during an energy minimization, invoked by the "minimize"_minimize.html command. Note that if you diff --git a/doc/src/fix_langevin.txt b/doc/src/fix_langevin.txt index 6ab236e572..769b188604 100644 --- a/doc/src/fix_langevin.txt +++ b/doc/src/fix_langevin.txt @@ -101,7 +101,7 @@ should not normally be used on atoms that also have their temperature controlled by another fix - e.g. by "fix nvt"_fix_nh.html or "fix temp/rescale"_fix_temp_rescale.html commands. -See "this howto section"_Section_howto.html#howto_16 of the manual for +See the "Howto thermostat"_Howto_thermostat.html doc page for a discussion of different ways to compute temperature and perform thermostatting. @@ -305,10 +305,10 @@ output"_thermo_style.html. Note that use of this option requires setting the {tally} keyword to {yes}. This fix computes a global scalar which can be accessed by various -"output commands"_Section_howto.html#howto_15. The scalar is the -cumulative energy change due to this fix. The scalar value -calculated by this fix is "extensive". Note that calculation of this -quantity requires setting the {tally} keyword to {yes}. +"output commands"_Howto_output.html. The scalar is the cumulative +energy change due to this fix. The scalar value calculated by this +fix is "extensive". Note that calculation of this quantity requires +setting the {tally} keyword to {yes}. This fix can ramp its target temperature over multiple runs, using the {start} and {stop} keywords of the "run"_run.html command. See the diff --git a/doc/src/fix_langevin_drude.txt b/doc/src/fix_langevin_drude.txt index c85ff24c96..bda8ec7881 100644 --- a/doc/src/fix_langevin_drude.txt +++ b/doc/src/fix_langevin_drude.txt @@ -44,8 +44,9 @@ fix 1 all langevin/drude 298.15 100.0 19377 5.0 10.0 83451 zero yes :pre Apply two Langevin thermostats as described in "(Jiang)"_#Jiang1 for thermalizing the reduced degrees of freedom of Drude oscillators. This link describes how to use the "thermalized Drude oscillator -model"_tutorial_drude.html in LAMMPS and polarizable models in LAMMPS -are discussed in "this Section"_Section_howto.html#howto_25. +model"_Howto_drude.html in LAMMPS and polarizable models in LAMMPS +are discussed on the "Howto polarizable"_Howto_polarizable.html doc +page. Drude oscillators are a way to simulate polarizables atoms, by splitting them into a core and a Drude particle bound by a harmonic @@ -99,8 +100,8 @@ Likewise, this fix should not normally be used on atoms that also have their temperature controlled by another fix - e.g. by "fix nvt"_fix_nh.html or "fix temp/rescale"_fix_temp_rescale.html commands. -See "this howto section"_Section_howto.html#howto_16 of the manual for -a discussion of different ways to compute temperature and perform +See the "Howto thermostat"_Howto_thermostat.html doc page for a +discussion of different ways to compute temperature and perform thermostating. :line diff --git a/doc/src/fix_langevin_eff.txt b/doc/src/fix_langevin_eff.txt index 4a50bfae54..ef22e99bcf 100644 --- a/doc/src/fix_langevin_eff.txt +++ b/doc/src/fix_langevin_eff.txt @@ -79,10 +79,10 @@ output"_thermo_style.html. Note that use of this option requires setting the {tally} keyword to {yes}. This fix computes a global scalar which can be accessed by various -"output commands"_Section_howto.html#howto_15. The scalar is the -cumulative energy change due to this fix. The scalar value -calculated by this fix is "extensive". Note that calculation of this -quantity requires setting the {tally} keyword to {yes}. +"output commands"_Howto_output.html. The scalar is the cumulative +energy change due to this fix. The scalar value calculated by this +fix is "extensive". Note that calculation of this quantity requires +setting the {tally} keyword to {yes}. This fix can ramp its target temperature over multiple runs, using the {start} and {stop} keywords of the "run"_run.html command. See the diff --git a/doc/src/fix_latte.txt b/doc/src/fix_latte.txt index 4edd610546..4f7e99dea8 100644 --- a/doc/src/fix_latte.txt +++ b/doc/src/fix_latte.txt @@ -118,9 +118,9 @@ of "thermodynamic output"_thermo_style.html. The default is {virial yes} This fix computes a global scalar which can be accessed by various -"output commands"_Section_howto.html#howto_15. The scalar is the -potential energy discussed above. The scalar value calculated by this -fix is "extensive". +"output commands"_Howto_output.html. The scalar is the potential +energy discussed above. The scalar value calculated by this fix is +"extensive". No parameter of this fix can be used with the {start/stop} keywords of the "run"_run.html command. diff --git a/doc/src/fix_lb_fluid.txt b/doc/src/fix_lb_fluid.txt index fc6203b0f2..925ca991c4 100644 --- a/doc/src/fix_lb_fluid.txt +++ b/doc/src/fix_lb_fluid.txt @@ -299,9 +299,9 @@ is written to the main LAMMPS "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored by this fix for -access by various "output commands"_Section_howto.html#howto_15. No -parameter of this fix can be used with the {start/stop} keywords of -the "run"_run.html command. This fix is not invoked during "energy +access by various "output commands"_Howto_output.html. No parameter +of this fix can be used with the {start/stop} keywords of the +"run"_run.html command. This fix is not invoked during "energy minimization"_minimize.html. [Restrictions:] diff --git a/doc/src/fix_lb_momentum.txt b/doc/src/fix_lb_momentum.txt index 97965e870d..78a1f497eb 100644 --- a/doc/src/fix_lb_momentum.txt +++ b/doc/src/fix_lb_momentum.txt @@ -49,10 +49,10 @@ dimension. No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can be -used with the {start/stop} keywords of the "run"_run.html command. -This fix is not invoked during "energy minimization"_minimize.html. +by this fix for access by various "output commands"_Howto_output.html. +No parameter of this fix can be used with the {start/stop} keywords of +the "run"_run.html command. This fix is not invoked during "energy +minimization"_minimize.html. [Restrictions:] diff --git a/doc/src/fix_lb_pc.txt b/doc/src/fix_lb_pc.txt index d2b6aafaab..f93d02f677 100644 --- a/doc/src/fix_lb_pc.txt +++ b/doc/src/fix_lb_pc.txt @@ -34,10 +34,10 @@ algorithm if the force coupling constant has been set by default. No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can be -used with the {start/stop} keywords of the "run"_run.html command. -This fix is not invoked during "energy minimization"_minimize.html. +by this fix for access by various "output commands"_Howto_output.html. +No parameter of this fix can be used with the {start/stop} keywords of +the "run"_run.html command. This fix is not invoked during "energy +minimization"_minimize.html. [Restrictions:] diff --git a/doc/src/fix_lb_rigid_pc_sphere.txt b/doc/src/fix_lb_rigid_pc_sphere.txt index 468ebe1ff5..50e91df849 100644 --- a/doc/src/fix_lb_rigid_pc_sphere.txt +++ b/doc/src/fix_lb_rigid_pc_sphere.txt @@ -80,12 +80,12 @@ assumes the constituent atoms are point particles); see No information about the {rigid} and {rigid/nve} fixes are written to "binary restart files"_restart.html. -Similar to the "fix rigid"_fix_rigid.html command: The rigid -fix computes a global scalar which can be accessed by various "output -commands"_Section_howto.html#howto_15. The scalar value calculated by -these fixes is "intensive". The scalar is the current temperature of -the collection of rigid bodies. This is averaged over all rigid -bodies and their translational and rotational degrees of freedom. The +Similar to the "fix rigid"_fix_rigid.html command: The rigid fix +computes a global scalar which can be accessed by various "output +commands"_Howto_output.html. The scalar value calculated by these +fixes is "intensive". The scalar is the current temperature of the +collection of rigid bodies. This is averaged over all rigid bodies +and their translational and rotational degrees of freedom. The translational energy of a rigid body is 1/2 m v^2, where m = total mass of the body and v = the velocity of its center of mass. The rotational energy of a rigid body is 1/2 I w^2, where I = the moment @@ -94,17 +94,17 @@ of freedom constrained by the {force} and {torque} keywords are removed from this calculation. All of these fixes compute a global array of values which can be -accessed by various "output commands"_Section_howto.html#howto_15. -The number of rows in the array is equal to the number of rigid -bodies. The number of columns is 15. Thus for each rigid body, 15 -values are stored: the xyz coords of the center of mass (COM), the xyz -components of the COM velocity, the xyz components of the force acting -on the COM, the xyz components of the torque acting on the COM, and -the xyz image flags of the COM, which have the same meaning as image -flags for atom positions (see the "dump" command). The force and -torque values in the array are not affected by the {force} and -{torque} keywords in the fix rigid command; they reflect values before -any changes are made by those keywords. +accessed by various "output commands"_Howto_output.html. The number +of rows in the array is equal to the number of rigid bodies. The +number of columns is 15. Thus for each rigid body, 15 values are +stored: the xyz coords of the center of mass (COM), the xyz components +of the COM velocity, the xyz components of the force acting on the +COM, the xyz components of the torque acting on the COM, and the xyz +image flags of the COM, which have the same meaning as image flags for +atom positions (see the "dump" command). The force and torque values +in the array are not affected by the {force} and {torque} keywords in +the fix rigid command; they reflect values before any changes are made +by those keywords. The ordering of the rigid bodies (by row in the array) is as follows. For the {single} keyword there is just one rigid body. For the diff --git a/doc/src/fix_lb_viscous.txt b/doc/src/fix_lb_viscous.txt index fcc69d2b43..27f089496e 100644 --- a/doc/src/fix_lb_viscous.txt +++ b/doc/src/fix_lb_viscous.txt @@ -57,9 +57,9 @@ As described in the "fix viscous"_fix_viscous.html documentation: "No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. +by this fix for access by various "output commands"_Howto_output.html. +No parameter of this fix can be used with the {start/stop} keywords of +the "run"_run.html command. The forces due to this fix are imposed during an energy minimization, invoked by the "minimize"_minimize.html command. This fix should only diff --git a/doc/src/fix_lineforce.txt b/doc/src/fix_lineforce.txt index 65672fc5a5..ad651862f6 100644 --- a/doc/src/fix_lineforce.txt +++ b/doc/src/fix_lineforce.txt @@ -35,9 +35,9 @@ it should continue to move along the line thereafter. No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. +by this fix for access by various "output commands"_Howto_output.html. +No parameter of this fix can be used with the {start/stop} keywords of +the "run"_run.html command. The forces due to this fix are imposed during an energy minimization, invoked by the "minimize"_minimize.html command. diff --git a/doc/src/fix_manifoldforce.txt b/doc/src/fix_manifoldforce.txt index 5fc25167a7..fe8a04051b 100644 --- a/doc/src/fix_manifoldforce.txt +++ b/doc/src/fix_manifoldforce.txt @@ -36,10 +36,10 @@ I have found that only {hftn} and {quickmin} with a very small time step perform No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. -This fix is invoked during "energy minimization"_minimize.html. +by this fix for access by various "output commands"_Howto_output.html. +No parameter of this fix can be used with the {start/stop} keywords of +the "run"_run.html command. This fix is invoked during "energy +minimization"_minimize.html. :line diff --git a/doc/src/fix_meso.txt b/doc/src/fix_meso.txt index 85f5838dd2..95f58bedaa 100644 --- a/doc/src/fix_meso.txt +++ b/doc/src/fix_meso.txt @@ -34,10 +34,10 @@ LAMMPS. No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. -This fix is not invoked during "energy minimization"_minimize.html. +by this fix for access by various "output commands"_Howto_output.html. +No parameter of this fix can be used with the {start/stop} keywords of +the "run"_run.html command. This fix is not invoked during "energy +minimization"_minimize.html. [Restrictions:] diff --git a/doc/src/fix_meso_stationary.txt b/doc/src/fix_meso_stationary.txt index 5b83573bc8..3b197c079f 100644 --- a/doc/src/fix_meso_stationary.txt +++ b/doc/src/fix_meso_stationary.txt @@ -35,10 +35,10 @@ LAMMPS. No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. -This fix is not invoked during "energy minimization"_minimize.html. +by this fix for access by various "output commands"_Howto_output.html. +No parameter of this fix can be used with the {start/stop} keywords of +the "run"_run.html command. This fix is not invoked during "energy +minimization"_minimize.html. [Restrictions:] diff --git a/doc/src/fix_momentum.txt b/doc/src/fix_momentum.txt index aa5199ac14..28fd2addf2 100644 --- a/doc/src/fix_momentum.txt +++ b/doc/src/fix_momentum.txt @@ -83,10 +83,10 @@ instructions on how to use the accelerated styles effectively. No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. -This fix is not invoked during "energy minimization"_minimize.html. +by this fix for access by various "output commands"_Howto_output.html. +No parameter of this fix can be used with the {start/stop} keywords of +the "run"_run.html command. This fix is not invoked during "energy +minimization"_minimize.html. [Restrictions:] none diff --git a/doc/src/fix_move.txt b/doc/src/fix_move.txt index 7cb40ad132..9a1d25b623 100644 --- a/doc/src/fix_move.txt +++ b/doc/src/fix_move.txt @@ -203,10 +203,9 @@ None of the "fix_modify"_fix_modify.html options are relevant to this fix. This fix produces a per-atom array which can be accessed by various -"output commands"_Section_howto.html#howto_15. The number of columns -for each atom is 3, and the columns store the original unwrapped x,y,z -coords of each atom. The per-atom values can be accessed on any -timestep. +"output commands"_Howto_output.html. The number of columns for each +atom is 3, and the columns store the original unwrapped x,y,z coords +of each atom. The per-atom values can be accessed on any timestep. No parameter of this fix can be used with the {start/stop} keywords of the "run"_run.html command. This fix is not invoked during "energy diff --git a/doc/src/fix_msst.txt b/doc/src/fix_msst.txt index 310692669a..d79b549580 100644 --- a/doc/src/fix_msst.txt +++ b/doc/src/fix_msst.txt @@ -156,8 +156,8 @@ thermo_style custom step temp ke pe lz pzz etotal v_dhug v_dray v_lgr_vel v_ These fixes compute a global scalar and a global vector of 4 quantities, which can be accessed by various "output -commands"_Section_howto.html#howto_15. The scalar values calculated -by this fix are "extensive"; the vector values are "intensive". +commands"_Howto_output.html. The scalar values calculated by this fix +are "extensive"; the vector values are "intensive". [Restrictions:] diff --git a/doc/src/fix_mvv_dpd.txt b/doc/src/fix_mvv_dpd.txt index fb3c6fe888..7a07642c54 100644 --- a/doc/src/fix_mvv_dpd.txt +++ b/doc/src/fix_mvv_dpd.txt @@ -69,10 +69,10 @@ addition to position and velocity, and must be used with the No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. -This fix is not invoked during "energy minimization"_minimize.html. +by this fix for access by various "output commands"_Howto_output.html. +No parameter of this fix can be used with the {start/stop} keywords of +the "run"_run.html command. This fix is not invoked during "energy +minimization"_minimize.html. [Restrictions:] diff --git a/doc/src/fix_neb.txt b/doc/src/fix_neb.txt index 5d18c39d99..5cfefbf819 100644 --- a/doc/src/fix_neb.txt +++ b/doc/src/fix_neb.txt @@ -43,9 +43,9 @@ Add nudging forces to atoms in the group for a multi-replica simulation run via the "neb"_neb.html command to perform a nudged elastic band (NEB) calculation for finding the transition state. Hi-level explanations of NEB are given with the "neb"_neb.html command -and in "Section_howto 5"_Section_howto.html#howto_5 of the manual. -The fix neb command must be used with the "neb" command and defines -how inter-replica nudging forces are computed. A NEB calculation is +and on the "Howto replica"_Howto_replica.html doc page. The fix neb +command must be used with the "neb" command and defines how +inter-replica nudging forces are computed. A NEB calculation is divided in two stages. In the first stage n replicas are relaxed toward a MEP until convergence. In the second stage, the climbing image scheme (see "(Henkelman2)"_#Henkelman2) is enabled, so that the @@ -192,9 +192,9 @@ target energy. No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. +by this fix for access by various "output commands"_Howto_output.html. +No parameter of this fix can be used with the {start/stop} keywords of +the "run"_run.html command. The forces due to this fix are imposed during an energy minimization, as invoked by the "minimize"_minimize.html command via the diff --git a/doc/src/fix_nh.txt b/doc/src/fix_nh.txt index e3a39c6bc6..d18f4a3e16 100644 --- a/doc/src/fix_nh.txt +++ b/doc/src/fix_nh.txt @@ -386,9 +386,10 @@ have their temperature controlled by another fix - e.g. by "fix langevin"_fix_nh.html or "fix temp/rescale"_fix_temp_rescale.html commands. -See "this howto section"_Section_howto.html#howto_16 of the manual for -a discussion of different ways to compute temperature and perform -thermostatting and barostatting. +See the "Howto thermostat"_Howto_thermostat.html and "Howto +barostat"_Howto_barostat.html doc pages for a discussion of different +ways to compute temperature and perform thermostatting and +barostatting. :line @@ -537,9 +538,9 @@ and barostatting to the system's potential energy as part of "thermodynamic output"_thermo_style.html. These fixes compute a global scalar and a global vector of quantities, -which can be accessed by various "output -commands"_Section_howto.html#howto_15. The scalar value calculated by -these fixes is "extensive"; the vector values are "intensive". +which can be accessed by various "output commands"_Howto_output.html. +The scalar value calculated by these fixes is "extensive"; the vector +values are "intensive". The scalar is the cumulative energy change due to the fix. diff --git a/doc/src/fix_nphug.txt b/doc/src/fix_nphug.txt index 4f696e9590..1276a5697d 100644 --- a/doc/src/fix_nphug.txt +++ b/doc/src/fix_nphug.txt @@ -192,9 +192,9 @@ included in the definition of internal energy E when calculating the value of Delta in the above equation. These fixes compute a global scalar and a global vector of quantities, -which can be accessed by various "output -commands"_Section_howto.html#howto_15. The scalar value calculated by -these fixes is "extensive"; the vector values are "intensive". +which can be accessed by various "output commands"_Howto_output.html. +The scalar value calculated by these fixes is "extensive"; the vector +values are "intensive". The scalar is the cumulative energy change due to the fix. diff --git a/doc/src/fix_nve.txt b/doc/src/fix_nve.txt index ac9cb53b50..8aa4197a60 100644 --- a/doc/src/fix_nve.txt +++ b/doc/src/fix_nve.txt @@ -58,10 +58,10 @@ instructions on how to use the accelerated styles effectively. No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. -This fix is not invoked during "energy minimization"_minimize.html. +by this fix for access by various "output commands"_Howto_output.html. +No parameter of this fix can be used with the {start/stop} keywords of +the "run"_run.html command. This fix is not invoked during "energy +minimization"_minimize.html. [Restrictions:] none diff --git a/doc/src/fix_nve_asphere.txt b/doc/src/fix_nve_asphere.txt index 5be7a7aa68..b9ee48f9dd 100644 --- a/doc/src/fix_nve_asphere.txt +++ b/doc/src/fix_nve_asphere.txt @@ -35,10 +35,10 @@ assumes point particles and only updates their position and velocity. No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. -This fix is not invoked during "energy minimization"_minimize.html. +by this fix for access by various "output commands"_Howto_output.html. +No parameter of this fix can be used with the {start/stop} keywords of +the "run"_run.html command. This fix is not invoked during "energy +minimization"_minimize.html. :line diff --git a/doc/src/fix_nve_asphere_noforce.txt b/doc/src/fix_nve_asphere_noforce.txt index 5f1b271546..164e3db104 100644 --- a/doc/src/fix_nve_asphere_noforce.txt +++ b/doc/src/fix_nve_asphere_noforce.txt @@ -38,10 +38,10 @@ Dynamics, since the velocity and angular momentum are updated by the No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. -This fix is not invoked during "energy minimization"_minimize.html. +by this fix for access by various "output commands"_Howto_output.html. +No parameter of this fix can be used with the {start/stop} keywords of +the "run"_run.html command. This fix is not invoked during "energy +minimization"_minimize.html. [Restrictions:] diff --git a/doc/src/fix_nve_body.txt b/doc/src/fix_nve_body.txt index 604b5391cd..3696425374 100644 --- a/doc/src/fix_nve_body.txt +++ b/doc/src/fix_nve_body.txt @@ -24,9 +24,9 @@ fix 1 all nve/body :pre Perform constant NVE integration to update position, velocity, orientation, and angular velocity for body particles in the group each timestep. V is volume; E is energy. This creates a system trajectory -consistent with the microcanonical ensemble. See "Section -6.14"_Section_howto.html#howto_14 of the manual and the "body"_body.html -doc page for more details on using body particles. +consistent with the microcanonical ensemble. See the "Howto +body"_Howto_body.html doc page for more details on using body +particles. This fix differs from the "fix nve"_fix_nve.html command, which assumes point particles and only updates their position and velocity. @@ -36,10 +36,10 @@ assumes point particles and only updates their position and velocity. No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. -This fix is not invoked during "energy minimization"_minimize.html. +by this fix for access by various "output commands"_Howto_output.html. +No parameter of this fix can be used with the {start/stop} keywords of +the "run"_run.html command. This fix is not invoked during "energy +minimization"_minimize.html. [Restrictions:] diff --git a/doc/src/fix_nve_eff.txt b/doc/src/fix_nve_eff.txt index 156f184dac..608e5e12ad 100644 --- a/doc/src/fix_nve_eff.txt +++ b/doc/src/fix_nve_eff.txt @@ -35,10 +35,10 @@ of electrons are also updated. No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. -This fix is not invoked during "energy minimization"_minimize.html. +by this fix for access by various "output commands"_Howto_output.html. +No parameter of this fix can be used with the {start/stop} keywords of +the "run"_run.html command. This fix is not invoked during "energy +minimization"_minimize.html. [Restrictions:] diff --git a/doc/src/fix_nve_limit.txt b/doc/src/fix_nve_limit.txt index 2ecec83e9c..ffaffd59b7 100644 --- a/doc/src/fix_nve_limit.txt +++ b/doc/src/fix_nve_limit.txt @@ -63,14 +63,14 @@ files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. This fix computes a global scalar which can be accessed by various -"output commands"_Section_howto.html#howto_15. The scalar is the -count of how many updates of atom's velocity/position were limited by -the maximum distance criterion. This should be roughly the number of -atoms so affected, except that updates occur at both the beginning and -end of a timestep in a velocity Verlet timestepping algorithm. This -is a cumulative quantity for the current run, but is re-initialized to -zero each time a run is performed. The scalar value calculated by -this fix is "extensive". +"output commands"_Howto_output.html. The scalar is the count of how +many updates of atom's velocity/position were limited by the maximum +distance criterion. This should be roughly the number of atoms so +affected, except that updates occur at both the beginning and end of a +timestep in a velocity Verlet timestepping algorithm. This is a +cumulative quantity for the current run, but is re-initialized to zero +each time a run is performed. The scalar value calculated by this fix +is "extensive". No parameter of this fix can be used with the {start/stop} keywords of the "run"_run.html command. This fix is not invoked during "energy diff --git a/doc/src/fix_nve_line.txt b/doc/src/fix_nve_line.txt index ac5206aa5c..a919e648e1 100644 --- a/doc/src/fix_nve_line.txt +++ b/doc/src/fix_nve_line.txt @@ -24,9 +24,9 @@ fix 1 all nve/line :pre Perform constant NVE integration to update position, velocity, orientation, and angular velocity for line segment particles in the group each timestep. V is volume; E is energy. This creates a system -trajectory consistent with the microcanonical ensemble. See -"Section 6.14"_Section_howto.html#howto_14 of the manual for an -overview of using line segment particles. +trajectory consistent with the microcanonical ensemble. See "Howto +spherical"_Howto_spherical.html doc page for an overview of using line +segment particles. This fix differs from the "fix nve"_fix_nve.html command, which assumes point particles and only updates their position and velocity. @@ -36,10 +36,10 @@ assumes point particles and only updates their position and velocity. No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. -This fix is not invoked during "energy minimization"_minimize.html. +by this fix for access by various "output commands"_Howto_output.html. +No parameter of this fix can be used with the {start/stop} keywords of +the "run"_run.html command. This fix is not invoked during "energy +minimization"_minimize.html. [Restrictions:] diff --git a/doc/src/fix_nve_manifold_rattle.txt b/doc/src/fix_nve_manifold_rattle.txt index e032a7e1cc..89922ea80d 100644 --- a/doc/src/fix_nve_manifold_rattle.txt +++ b/doc/src/fix_nve_manifold_rattle.txt @@ -40,7 +40,7 @@ the dynamics of particles constrained to curved surfaces can be studied. If combined with "fix langevin"_fix_langevin.html, this generates Brownian motion of particles constrained to a curved surface. For a list of currently supported manifolds and their -parameters, see "manifolds"_manifolds.html. +parameters, see the "Howto manifold"_Howto_manifold.html doc page. Note that the particles must initially be close to the manifold in question. If not, RATTLE will not be able to iterate until the @@ -68,10 +68,10 @@ conserved. No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. -This fix is not invoked during "energy minimization"_minimize.html. +by this fix for access by various "output commands"_Howto_output.html. +No parameter of this fix can be used with the {start/stop} keywords of +the "run"_run.html command. This fix is not invoked during "energy +minimization"_minimize.html. :line diff --git a/doc/src/fix_nve_noforce.txt b/doc/src/fix_nve_noforce.txt index a0dbcc80f1..c1a4f76eaf 100644 --- a/doc/src/fix_nve_noforce.txt +++ b/doc/src/fix_nve_noforce.txt @@ -40,10 +40,10 @@ fcm() group function to compute the total force on the group of atoms. No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. -This fix is not invoked during "energy minimization"_minimize.html. +by this fix for access by various "output commands"_Howto_output.html. +No parameter of this fix can be used with the {start/stop} keywords of +the "run"_run.html command. This fix is not invoked during "energy +minimization"_minimize.html. [Restrictions:] none diff --git a/doc/src/fix_nve_sphere.txt b/doc/src/fix_nve_sphere.txt index cfe73a854d..36c4178de9 100644 --- a/doc/src/fix_nve_sphere.txt +++ b/doc/src/fix_nve_sphere.txt @@ -89,10 +89,10 @@ instructions on how to use the accelerated styles effectively. No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. -This fix is not invoked during "energy minimization"_minimize.html. +by this fix for access by various "output commands"_Howto_output.html. +No parameter of this fix can be used with the {start/stop} keywords of +the "run"_run.html command. This fix is not invoked during "energy +minimization"_minimize.html. [Restrictions:] diff --git a/doc/src/fix_nve_tri.txt b/doc/src/fix_nve_tri.txt index cee27e2fa4..9c03eb872a 100644 --- a/doc/src/fix_nve_tri.txt +++ b/doc/src/fix_nve_tri.txt @@ -23,10 +23,10 @@ fix 1 all nve/tri :pre Perform constant NVE integration to update position, velocity, orientation, and angular momentum for triangular particles in the -group each timestep. V is volume; E is energy. This creates a -system trajectory consistent with the microcanonical ensemble. See -"Section 6.14"_Section_howto.html#howto_14 of the manual for an -overview of using triangular particles. +group each timestep. V is volume; E is energy. This creates a system +trajectory consistent with the microcanonical ensemble. See the +"Howto spherical"_Howto_spherical.html doc page for an overview of +using triangular particles. This fix differs from the "fix nve"_fix_nve.html command, which assumes point particles and only updates their position and velocity. @@ -36,10 +36,10 @@ assumes point particles and only updates their position and velocity. No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. -This fix is not invoked during "energy minimization"_minimize.html. +by this fix for access by various "output commands"_Howto_output.html. +No parameter of this fix can be used with the {start/stop} keywords of +the "run"_run.html command. This fix is not invoked during "energy +minimization"_minimize.html. [Restrictions:] diff --git a/doc/src/fix_nvk.txt b/doc/src/fix_nvk.txt index 49fd8217ab..2106ee5235 100644 --- a/doc/src/fix_nvk.txt +++ b/doc/src/fix_nvk.txt @@ -42,10 +42,10 @@ energy prior to this fix. No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. -This fix is not invoked during "energy minimization"_minimize.html. +by this fix for access by various "output commands"_Howto_output.html. +No parameter of this fix can be used with the {start/stop} keywords of +the "run"_run.html command. This fix is not invoked during "energy +minimization"_minimize.html. [Restrictions:] diff --git a/doc/src/fix_nvt_manifold_rattle.txt b/doc/src/fix_nvt_manifold_rattle.txt index a620648a46..4261f9a4db 100644 --- a/doc/src/fix_nvt_manifold_rattle.txt +++ b/doc/src/fix_nvt_manifold_rattle.txt @@ -37,9 +37,13 @@ fix 1 all nvt/manifold/rattle 1e-4 10 cylinder 3.0 temp 1.0 1.0 10.0 [Description:] -This fix combines the RATTLE-based "(Andersen)"_#Andersen2 time integrator of "fix nve/manifold/rattle"_fix_nve_manifold_rattle.html "(Paquay)"_#Paquay3 with a Nose-Hoover-chain thermostat to sample the -canonical ensemble of particles constrained to a curved surface (manifold). This sampling does suffer from discretization bias of O(dt). -For a list of currently supported manifolds and their parameters, see "manifolds"_manifolds.html +This fix combines the RATTLE-based "(Andersen)"_#Andersen2 time +integrator of "fix nve/manifold/rattle"_fix_nve_manifold_rattle.html +"(Paquay)"_#Paquay3 with a Nose-Hoover-chain thermostat to sample the +canonical ensemble of particles constrained to a curved surface +(manifold). This sampling does suffer from discretization bias of +O(dt). For a list of currently supported manifolds and their +parameters, see the "Howto manifold"_Howto_manifold.html doc page. :line @@ -48,10 +52,10 @@ For a list of currently supported manifolds and their parameters, see "manifolds No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. -This fix is not invoked during "energy minimization"_minimize.html. +by this fix for access by various "output commands"_Howto_output.html. +No parameter of this fix can be used with the {start/stop} keywords of +the "run"_run.html command. This fix is not invoked during "energy +minimization"_minimize.html. :line diff --git a/doc/src/fix_oneway.txt b/doc/src/fix_oneway.txt index 2d85c581eb..d9217ab14b 100644 --- a/doc/src/fix_oneway.txt +++ b/doc/src/fix_oneway.txt @@ -43,10 +43,10 @@ membrane, or as an implementation of Maxwell's demon. No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. -This fix is not invoked during "energy minimization"_minimize.html. +by this fix for access by various "output commands"_Howto_output.html. +No parameter of this fix can be used with the {start/stop} keywords of +the "run"_run.html command. This fix is not invoked during "energy +minimization"_minimize.html. [Restrictions:] none diff --git a/doc/src/fix_orient.txt b/doc/src/fix_orient.txt index 20ff94866e..c57cccd322 100644 --- a/doc/src/fix_orient.txt +++ b/doc/src/fix_orient.txt @@ -135,14 +135,14 @@ fixes. This allows to set at which level of the "r-RESPA"_run_style.html integrator a fix is adding its forces. Default is the outermost level. This fix calculates a global scalar which can be accessed by various -"output commands"_Section_howto.html#howto_15. The scalar is the -potential energy change due to this fix. The scalar value calculated -by this fix is "extensive". +"output commands"_Howto_output.html. The scalar is the potential +energy change due to this fix. The scalar value calculated by this +fix is "extensive". This fix also calculates a per-atom array which can be accessed by -various "output commands"_Section_howto.html#howto_15. The array -stores the order parameter Xi and normalized order parameter (0 to 1) -for each atom. The per-atom values can be accessed on any timestep. +various "output commands"_Howto_output.html. The array stores the +order parameter Xi and normalized order parameter (0 to 1) for each +atom. The per-atom values can be accessed on any timestep. No parameter of this fix can be used with the {start/stop} keywords of the "run"_run.html command. This fix is not invoked during "energy diff --git a/doc/src/fix_phonon.txt b/doc/src/fix_phonon.txt index aad6c2bfaa..63df4e6801 100644 --- a/doc/src/fix_phonon.txt +++ b/doc/src/fix_phonon.txt @@ -150,7 +150,7 @@ fix. You can use it to change the temperature compute from thermo_temp to the one that reflects the true temperature of atoms in the group. No global scalar or vector or per-atom quantities are stored by this -fix for access by various "output commands"_Section_howto.html#howto_15. +fix for access by various "output commands"_Howto_output.html. Instead, this fix outputs its initialization information (including mapping information) and the calculated dynamical matrices to the file diff --git a/doc/src/fix_pimd.txt b/doc/src/fix_pimd.txt index 38022e4c7d..8958063d2e 100644 --- a/doc/src/fix_pimd.txt +++ b/doc/src/fix_pimd.txt @@ -103,14 +103,13 @@ is appropriate for most situations. The PIMD algorithm in LAMMPS is implemented as a hyper-parallel scheme as described in "(Calhoun)"_#Calhoun. In LAMMPS this is done by using -"multi-replica feature"_Section_howto.html#howto_5 in LAMMPS, where -each quasi-particle system is stored and simulated on a separate -partition of processors. The following diagram illustrates this -approach. The original system with 2 ring polymers is shown in red. -Since each ring has 4 quasi-beads (imaginary time slices), there are 4 -replicas of the system, each running on one of the 4 partitions of -processors. Each replica (shown in green) owns one quasi-bead in each -ring. +"multi-replica feature"_Howto_replica.html in LAMMPS, where each +quasi-particle system is stored and simulated on a separate partition +of processors. The following diagram illustrates this approach. The +original system with 2 ring polymers is shown in red. Since each ring +has 4 quasi-beads (imaginary time slices), there are 4 replicas of the +system, each running on one of the 4 partitions of processors. Each +replica (shown in green) owns one quasi-bead in each ring. :c,image(JPG/pimd.jpg) diff --git a/doc/src/fix_planeforce.txt b/doc/src/fix_planeforce.txt index 67956c8b6d..4a74301066 100644 --- a/doc/src/fix_planeforce.txt +++ b/doc/src/fix_planeforce.txt @@ -35,9 +35,9 @@ should continue to move in the plane thereafter. No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. +by this fix for access by various "output commands"_Howto_output.html. +No parameter of this fix can be used with the {start/stop} keywords of +the "run"_run.html command. The forces due to this fix are imposed during an energy minimization, invoked by the "minimize"_minimize.html command. diff --git a/doc/src/fix_poems.txt b/doc/src/fix_poems.txt index 03abc058b8..0690923b45 100644 --- a/doc/src/fix_poems.txt +++ b/doc/src/fix_poems.txt @@ -114,9 +114,9 @@ early or late in a timestep, i.e. at the post-force stage or at the final-integrate stage, respectively. No global or per-atom quantities are stored by this fix for access by -various "output commands"_Section_howto.html#howto_15. No parameter -of this fix can be used with the {start/stop} keywords of the -"run"_run.html command. This fix is not invoked during "energy +various "output commands"_Howto_output.html. No parameter of this fix +can be used with the {start/stop} keywords of the "run"_run.html +command. This fix is not invoked during "energy minimization"_minimize.html. [Restrictions:] diff --git a/doc/src/fix_pour.txt b/doc/src/fix_pour.txt index 54f78287e0..4b86405522 100644 --- a/doc/src/fix_pour.txt +++ b/doc/src/fix_pour.txt @@ -237,9 +237,9 @@ appropriately. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored by this fix for -access by various "output commands"_Section_howto.html#howto_15. No -parameter of this fix can be used with the {start/stop} keywords of -the "run"_run.html command. This fix is not invoked during "energy +access by various "output commands"_Howto_output.html. No parameter +of this fix can be used with the {start/stop} keywords of the +"run"_run.html command. This fix is not invoked during "energy minimization"_minimize.html. [Restrictions:] diff --git a/doc/src/fix_precession_spin.txt b/doc/src/fix_precession_spin.txt index 4133d7dd57..bc18fa0e8c 100644 --- a/doc/src/fix_precession_spin.txt +++ b/doc/src/fix_precession_spin.txt @@ -67,8 +67,8 @@ to add this magnetic potential energy to the potential energy of the system, fix 1 all precession/spin zeeman 1.0 0.0 0.0 1.0 fix_modify 1 energy yes :pre -This fix computes a global scalar which can be accessed by various -"output commands"_Section_howto.html#howto_15. +This fix computes a global scalar which can be accessed by various +"output commands"_Howto_output.html. No information about this fix is written to "binary restart files"_restart.html. diff --git a/doc/src/fix_press_berendsen.txt b/doc/src/fix_press_berendsen.txt index 9c9da8ec7b..0e41abd1f8 100644 --- a/doc/src/fix_press_berendsen.txt +++ b/doc/src/fix_press_berendsen.txt @@ -58,9 +58,8 @@ to control the temperature, such as "fix nvt"_fix_nh.html or "fix langevin"_fix_langevin.html or "fix temp/berendsen"_fix_temp_berendsen.html. -See "this howto section"_Section_howto.html#howto_16 of the manual for -a discussion of different ways to compute temperature and perform -thermostatting and barostatting. +See the "Howto baroostat"_Howto_barostat.html doc page for a +discussion of different ways to perform barostatting. :line @@ -196,7 +195,7 @@ pressure. LAMMPS will warn you if you choose to compute temperature on a subset of atoms. No global or per-atom quantities are stored by this fix for access by -various "output commands"_Section_howto.html#howto_15. +various "output commands"_Howto_output.html. This fix can ramp its target pressure over multiple runs, using the {start} and {stop} keywords of the "run"_run.html command. See the diff --git a/doc/src/fix_print.txt b/doc/src/fix_print.txt index cf3b542833..f7a7b333c4 100644 --- a/doc/src/fix_print.txt +++ b/doc/src/fix_print.txt @@ -73,10 +73,10 @@ where ID is replaced with the fix-ID. No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. -This fix is not invoked during "energy minimization"_minimize.html. +by this fix for access by various "output commands"_Howto_output.html. +No parameter of this fix can be used with the {start/stop} keywords of +the "run"_run.html command. This fix is not invoked during "energy +minimization"_minimize.html. [Restrictions:] none diff --git a/doc/src/fix_property_atom.txt b/doc/src/fix_property_atom.txt index 95fc2c424d..624fc5f7df 100644 --- a/doc/src/fix_property_atom.txt +++ b/doc/src/fix_property_atom.txt @@ -200,18 +200,17 @@ added classes. :line -:link(isotopes) -Example for using per-atom masses with TIP4P water to study isotope -effects. When setting up simulations with the "TIP4P pair -styles"_Section_howto.html#howto_8 for water, you have to provide -exactly one atom type each to identify the water oxygen and hydrogen +:link(isotopes) Example for using per-atom masses with TIP4P water to +study isotope effects. When setting up simulations with the "TIP4P +pair styles"_Howto_tip4p.html for water, you have to provide exactly +one atom type each to identify the water oxygen and hydrogen atoms. Since the atom mass is normally tied to the atom type, this makes it impossible to study multiple isotopes in the same simulation. With {fix property/atom rmass} however, the per-type masses are replaced by per-atom masses. Asumming you have a working input deck -for regular TIP4P water, where water oxygen is atom type 1 and -water hydrogen is atom type 2, the following lines of input script -convert this to using per-atom masses: +for regular TIP4P water, where water oxygen is atom type 1 and water +hydrogen is atom type 2, the following lines of input script convert +this to using per-atom masses: fix Isotopes all property/atom rmass ghost yes set type 1 mass 15.9994 @@ -247,12 +246,12 @@ command for info on how to re-specify a fix in an input script that reads a restart file, so that the operation of the fix continues in an uninterrupted fashion. -None of the "fix_modify"_fix_modify.html options -are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. -This fix is not invoked during "energy minimization"_minimize.html. +None of the "fix_modify"_fix_modify.html options are relevant to this +fix. No global or per-atom quantities are stored by this fix for +access by various "output commands"_Howto_output.html. No parameter +of this fix can be used with the {start/stop} keywords of the +"run"_run.html command. This fix is not invoked during "energy +minimization"_minimize.html. [Restrictions:] none diff --git a/doc/src/fix_python_move.txt b/doc/src/fix_python_move.txt index f10f607a9b..2f49427a9e 100644 --- a/doc/src/fix_python_move.txt +++ b/doc/src/fix_python_move.txt @@ -83,10 +83,10 @@ Examples for how to do this are in the {examples/python} folder. No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. -This fix is not invoked during "energy minimization"_minimize.html. +by this fix for access by various "output commands"_Howto_output.html. +No parameter of this fix can be used with the {start/stop} keywords of +the "run"_run.html command. This fix is not invoked during "energy +minimization"_minimize.html. [Restrictions:] diff --git a/doc/src/fix_qbmsst.txt b/doc/src/fix_qbmsst.txt index 2c116fb0f8..56ace85e57 100644 --- a/doc/src/fix_qbmsst.txt +++ b/doc/src/fix_qbmsst.txt @@ -179,10 +179,10 @@ thermo_style custom step temp ke pe lz pzz etotal v_dhug v_dray v_lgr_vel v_ The global scalar under the entry f_fix_id is the quantity of thermo energy as an extra part of etot. This global scalar and the vector of 5 quantities can be accessed by various "output -commands"_Section_howto.html#howto_15. It is worth noting that the -temp keyword under the "thermo_style"_thermo_style.html command print -the instantaneous classical temperature Tcl as -described in the command "fix qtb"_fix_qtb.html. +commands"_Howto_output.html. It is worth noting that the temp keyword +under the "thermo_style"_thermo_style.html command print the +instantaneous classical temperature Tcl as described +in the command "fix qtb"_fix_qtb.html. :line diff --git a/doc/src/fix_qeq.txt b/doc/src/fix_qeq.txt index 194361e990..c142d4a06d 100644 --- a/doc/src/fix_qeq.txt +++ b/doc/src/fix_qeq.txt @@ -179,9 +179,8 @@ parameters. See the examples/qeq directory for some examples. No information about these fixes is written to "binary restart files"_restart.html. No global scalar or vector or per-atom quantities are stored by these fixes for access by various "output -commands"_Section_howto.html#howto_15. No parameter of these fixes -can be used with the {start/stop} keywords of the "run"_run.html -command. +commands"_Howto_output.html. No parameter of these fixes can be used +with the {start/stop} keywords of the "run"_run.html command. Thexe fixes are invoked during "energy minimization"_minimize.html. diff --git a/doc/src/fix_qeq_comb.txt b/doc/src/fix_qeq_comb.txt index 783dc3133c..0eb38fcae6 100644 --- a/doc/src/fix_qeq_comb.txt +++ b/doc/src/fix_qeq_comb.txt @@ -92,9 +92,9 @@ integrator the fix is performing charge equilibration. Default is the outermost level. This fix produces a per-atom vector which can be accessed by various -"output commands"_Section_howto.html#howto_15. The vector stores the -gradient of the charge on each atom. The per-atom values be accessed -on any timestep. +"output commands"_Howto_output.html. The vector stores the gradient +of the charge on each atom. The per-atom values be accessed on any +timestep. No parameter of this fix can be used with the {start/stop} keywords of the "run"_run.html command. diff --git a/doc/src/fix_qeq_reax.txt b/doc/src/fix_qeq_reax.txt index a534a66c09..ea25ddbf57 100644 --- a/doc/src/fix_qeq_reax.txt +++ b/doc/src/fix_qeq_reax.txt @@ -70,8 +70,8 @@ the {qeq/reax/omp} style. Otherwise they are processed separately. No information about this fix is written to "binary restart files"_restart.html. No global scalar or vector or per-atom quantities are stored by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. +commands"_Howto_output.html. No parameter of this fix can be used +with the {start/stop} keywords of the "run"_run.html command. This fix is invoked during "energy minimization"_minimize.html. diff --git a/doc/src/fix_qmmm.txt b/doc/src/fix_qmmm.txt index 1b4a850a42..5e730ac8af 100644 --- a/doc/src/fix_qmmm.txt +++ b/doc/src/fix_qmmm.txt @@ -46,9 +46,9 @@ No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global scalar or vector or per-atom quantities are stored by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. -This fix is not invoked during "energy minimization"_minimize.html. +commands"_Howto_output.html. No parameter of this fix can be used +with the {start/stop} keywords of the "run"_run.html command. This +fix is not invoked during "energy minimization"_minimize.html. [Restrictions:] diff --git a/doc/src/fix_reax_bonds.txt b/doc/src/fix_reax_bonds.txt index 50f0b77d52..2f7c38f815 100644 --- a/doc/src/fix_reax_bonds.txt +++ b/doc/src/fix_reax_bonds.txt @@ -62,10 +62,10 @@ version, but will also take longer to write. No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. -This fix is not invoked during "energy minimization"_minimize.html. +by this fix for access by various "output commands"_Howto_output.html. +No parameter of this fix can be used with the {start/stop} keywords of +the "run"_run.html command. This fix is not invoked during "energy +minimization"_minimize.html. :line diff --git a/doc/src/fix_reaxc_species.txt b/doc/src/fix_reaxc_species.txt index 75e4598ca5..4f1249744f 100644 --- a/doc/src/fix_reaxc_species.txt +++ b/doc/src/fix_reaxc_species.txt @@ -116,8 +116,8 @@ are relevant to this fix. This fix computes both a global vector of length 2 and a per-atom vector, either of which can be accessed by various "output -commands"_Section_howto.html#howto_15. The values in the global -vector are "intensive". +commands"_Howto_output.html. The values in the global vector are +"intensive". The 2 values in the global vector are as follows: diff --git a/doc/src/fix_recenter.txt b/doc/src/fix_recenter.txt index 342bed4251..a2477d11c7 100644 --- a/doc/src/fix_recenter.txt +++ b/doc/src/fix_recenter.txt @@ -94,13 +94,13 @@ files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. This fix computes a global scalar which can be accessed by various -"output commands"_Section_howto.html#howto_15. The scalar is the -distance the group is moved by fix recenter. +"output commands"_Howto_output.html. The scalar is the distance the +group is moved by fix recenter. This fix also computes global 3-vector which can be accessed by -various "output commands"_Section_howto.html#howto_15. The 3 -quantities in the vector are xyz components of displacement applied to -the group of atoms by the fix. +various "output commands"_Howto_output.html. The 3 quantities in the +vector are xyz components of displacement applied to the group of +atoms by the fix. The scalar and vector values calculated by this fix are "extensive". diff --git a/doc/src/fix_restrain.txt b/doc/src/fix_restrain.txt index 9de63defb7..b8cc7c0d45 100644 --- a/doc/src/fix_restrain.txt +++ b/doc/src/fix_restrain.txt @@ -187,8 +187,8 @@ added forces to be included in the total potential energy of the system (the quantity being minimized), you MUST enable the "fix_modify"_fix_modify.html {energy} option for this fix. -This fix computes a global scalar and a global vector of length 3, which -can be accessed by various "output commands"_Section_howto.html#howto_15. +This fix computes a global scalar and a global vector of length 3, +which can be accessed by various "output commands"_Howto_output.html. The scalar is the total potential energy for {all} the restraints as discussed above. The vector values are the sum of contributions to the following individual categories: diff --git a/doc/src/fix_rigid.txt b/doc/src/fix_rigid.txt index f3dd20daa3..a5f00c16e9 100644 --- a/doc/src/fix_rigid.txt +++ b/doc/src/fix_rigid.txt @@ -745,29 +745,29 @@ computed early or late in a timestep, i.e. at the post-force stage or at the final-integrate stage or the timestep, respectively. The 2 NVE rigid fixes compute a global scalar which can be accessed by -various "output commands"_Section_howto.html#howto_15. The scalar -value calculated by these fixes is "intensive". The scalar is the -current temperature of the collection of rigid bodies. This is -averaged over all rigid bodies and their translational and rotational -degrees of freedom. The translational energy of a rigid body is 1/2 m -v^2, where m = total mass of the body and v = the velocity of its -center of mass. The rotational energy of a rigid body is 1/2 I w^2, -where I = the moment of inertia tensor of the body and w = its angular -velocity. Degrees of freedom constrained by the {force} and {torque} -keywords are removed from this calculation, but only for the {rigid} -and {rigid/nve} fixes. +various "output commands"_Howto_output.html. The scalar value +calculated by these fixes is "intensive". The scalar is the current +temperature of the collection of rigid bodies. This is averaged over +all rigid bodies and their translational and rotational degrees of +freedom. The translational energy of a rigid body is 1/2 m v^2, where +m = total mass of the body and v = the velocity of its center of mass. +The rotational energy of a rigid body is 1/2 I w^2, where I = the +moment of inertia tensor of the body and w = its angular velocity. +Degrees of freedom constrained by the {force} and {torque} keywords +are removed from this calculation, but only for the {rigid} and +{rigid/nve} fixes. The 6 NVT, NPT, NPH rigid fixes compute a global scalar which can be -accessed by various "output commands"_Section_howto.html#howto_15. -The scalar value calculated by these fixes is "extensive". The scalar -is the cumulative energy change due to the thermostatting and -barostatting the fix performs. +accessed by various "output commands"_Howto_output.html. The scalar +value calculated by these fixes is "extensive". The scalar is the +cumulative energy change due to the thermostatting and barostatting +the fix performs. All of the {rigid} styles (not the {rigid/small} styles) compute a global array of values which can be accessed by various "output -commands"_Section_howto.html#howto_15. Similar information about the -bodies defined by the {rigid/small} styles can be accessed via the -"compute rigid/local"_compute_rigid_local.html command. +commands"_Howto_output.html. Similar information about the bodies +defined by the {rigid/small} styles can be accessed via the "compute +rigid/local"_compute_rigid_local.html command. The number of rows in the array is equal to the number of rigid bodies. The number of columns is 15. Thus for each rigid body, 15 diff --git a/doc/src/fix_setforce.txt b/doc/src/fix_setforce.txt index 0af1c92922..c6a01e5492 100644 --- a/doc/src/fix_setforce.txt +++ b/doc/src/fix_setforce.txt @@ -103,10 +103,10 @@ so that setforce values are not counted multiple times. Default is to to override forces at the outermost level. This fix computes a global 3-vector of forces, which can be accessed -by various "output commands"_Section_howto.html#howto_15. This is the -total force on the group of atoms before the forces on individual -atoms are changed by the fix. The vector values calculated by this -fix are "extensive". +by various "output commands"_Howto_output.html. This is the total +force on the group of atoms before the forces on individual atoms are +changed by the fix. The vector values calculated by this fix are +"extensive". No parameter of this fix can be used with the {start/stop} keywords of the "run"_run.html command. diff --git a/doc/src/fix_shake.txt b/doc/src/fix_shake.txt index 7428b30a14..9297bcc87a 100644 --- a/doc/src/fix_shake.txt +++ b/doc/src/fix_shake.txt @@ -195,10 +195,9 @@ No information about these fixes is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to these fixes. No global or per-atom quantities are stored by these fixes for access by various "output -commands"_Section_howto.html#howto_15. No parameter of these fixes -can be used with the {start/stop} keywords of the "run"_run.html -command. These fixes are not invoked during "energy -minimization"_minimize.html. +commands"_Howto_output.html. No parameter of these fixes can be used +with the {start/stop} keywords of the "run"_run.html command. These +fixes are not invoked during "energy minimization"_minimize.html. [Restrictions:] diff --git a/doc/src/fix_smd.txt b/doc/src/fix_smd.txt index cb4a40f0fd..e9403b22cc 100644 --- a/doc/src/fix_smd.txt +++ b/doc/src/fix_smd.txt @@ -111,12 +111,12 @@ this fix. This allows to set at which level of the "r-RESPA"_run_style.html integrator the fix is adding its forces. Default is the outermost level. This fix computes a vector list of 7 quantities, which can be accessed -by various "output commands"_Section_howto.html#howto_15. The -quantities in the vector are in this order: the x-, y-, and -z-component of the pulling force, the total force in direction of the -pull, the equilibrium distance of the spring, the distance between the -two reference points, and finally the accumulated PMF (the sum of -pulling forces times displacement). +by various "output commands"_Howto_output.html. The quantities in the +vector are in this order: the x-, y-, and z-component of the pulling +force, the total force in direction of the pull, the equilibrium +distance of the spring, the distance between the two reference points, +and finally the accumulated PMF (the sum of pulling forces times +displacement). The force is the total force on the group of atoms by the spring. In the case of the {couple} style, it is the force on the fix group diff --git a/doc/src/fix_smd_setvel.txt b/doc/src/fix_smd_setvel.txt index f93a7d0965..d64726d9b3 100644 --- a/doc/src/fix_smd_setvel.txt +++ b/doc/src/fix_smd_setvel.txt @@ -66,9 +66,9 @@ None of the "fix_modify"_fix_modify.html options are relevant to this fix. This fix computes a global 3-vector of forces, which can be accessed -by various "output commands"_Section_howto.html#howto_15. This is the -total force on the group of atoms. The vector values calculated by this -fix are "extensive". +by various "output commands"_Howto_output.html. This is the total +force on the group of atoms. The vector values calculated by this fix +are "extensive". No parameter of this fix can be used with the {start/stop} keywords of the "run"_run.html command. diff --git a/doc/src/fix_spring.txt b/doc/src/fix_spring.txt index 014a43aacc..047e5a6797 100644 --- a/doc/src/fix_spring.txt +++ b/doc/src/fix_spring.txt @@ -105,19 +105,19 @@ fix. This allows to set at which level of the "r-RESPA"_run_style.html integrator the fix is adding its forces. Default is the outermost level. This fix computes a global scalar which can be accessed by various -"output commands"_Section_howto.html#howto_15. The scalar is the -spring energy = 0.5 * K * r^2. +"output commands"_Howto_output.html. The scalar is the spring energy += 0.5 * K * r^2. This fix also computes global 4-vector which can be accessed by -various "output commands"_Section_howto.html#howto_15. The first 3 -quantities in the vector are xyz components of the total force added -to the group of atoms by the spring. In the case of the {couple} -style, it is the force on the fix group (group-ID) or the negative of -the force on the 2nd group (group-ID2). The 4th quantity in the -vector is the magnitude of the force added by the spring, as a -positive value if (r-R0) > 0 and a negative value if (r-R0) < 0. This -sign convention can be useful when using the spring force to compute a -potential of mean force (PMF). +various "output commands"_Howto_output.html. The first 3 quantities +in the vector are xyz components of the total force added to the group +of atoms by the spring. In the case of the {couple} style, it is the +force on the fix group (group-ID) or the negative of the force on the +2nd group (group-ID2). The 4th quantity in the vector is the +magnitude of the force added by the spring, as a positive value if +(r-R0) > 0 and a negative value if (r-R0) < 0. This sign convention +can be useful when using the spring force to compute a potential of +mean force (PMF). The scalar and vector values calculated by this fix are "extensive". diff --git a/doc/src/fix_spring_chunk.txt b/doc/src/fix_spring_chunk.txt index 7630a009dd..e46f299771 100644 --- a/doc/src/fix_spring_chunk.txt +++ b/doc/src/fix_spring_chunk.txt @@ -60,8 +60,8 @@ fix. This allows to set at which level of the "r-RESPA"_run_style.html integrator the fix is adding its forces. Default is the outermost level. This fix computes a global scalar which can be accessed by various -"output commands"_Section_howto.html#howto_15. The scalar is the -energy of all the springs, i.e. 0.5 * K * r^2 per-spring. +"output commands"_Howto_output.html. The scalar is the energy of all +the springs, i.e. 0.5 * K * r^2 per-spring. The scalar value calculated by this fix is "extensive". diff --git a/doc/src/fix_spring_rg.txt b/doc/src/fix_spring_rg.txt index bff6b38e7e..4afdc02d5a 100644 --- a/doc/src/fix_spring_rg.txt +++ b/doc/src/fix_spring_rg.txt @@ -51,10 +51,10 @@ the time the fix is specified, and that value is used as the target. No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. -This fix is not invoked during "energy minimization"_minimize.html. +by this fix for access by various "output commands"_Howto_output.html. +No parameter of this fix can be used with the {start/stop} keywords of +the "run"_run.html command. This fix is not invoked during "energy +minimization"_minimize.html. The "fix_modify"_fix_modify.html {respa} option is supported by this fix. This allows to set at which level of the "r-RESPA"_run_style.html diff --git a/doc/src/fix_spring_self.txt b/doc/src/fix_spring_self.txt index 68961a1512..e5b5c3dfd0 100644 --- a/doc/src/fix_spring_self.txt +++ b/doc/src/fix_spring_self.txt @@ -57,10 +57,10 @@ this fix. This allows to set at which level of the "r-RESPA"_run_style.html integrator the fix is adding its forces. Default is the outermost level. This fix computes a global scalar which can be accessed by various -"output commands"_Section_howto.html#howto_15. The scalar is an -energy which is the sum of the spring energy for each atom, where the -per-atom energy is 0.5 * K * r^2. The scalar value calculated by this -fix is "extensive". +"output commands"_Howto_output.html. The scalar is an energy which is +the sum of the spring energy for each atom, where the per-atom energy +is 0.5 * K * r^2. The scalar value calculated by this fix is +"extensive". No parameter of this fix can be used with the {start/stop} keywords of the "run"_run.html command. diff --git a/doc/src/fix_srd.txt b/doc/src/fix_srd.txt index 4e190234fd..7c5179fb3f 100644 --- a/doc/src/fix_srd.txt +++ b/doc/src/fix_srd.txt @@ -341,11 +341,11 @@ are relevant to this fix. This fix tabulates several SRD statistics which are stored in a vector of length 12, which can be accessed by various "output -commands"_Section_howto.html#howto_15. The vector values calculated -by this fix are "intensive", meaning they do not scale with the size -of the simulation. Technically, the first 8 do scale with the size of -the simulation, but treating them as intensive means they are not -scaled when printed as part of thermodynamic output. +commands"_Howto_output.html. The vector values calculated by this fix +are "intensive", meaning they do not scale with the size of the +simulation. Technically, the first 8 do scale with the size of the +simulation, but treating them as intensive means they are not scaled +when printed as part of thermodynamic output. These are the 12 quantities. All are values for the current timestep, except for quantity 5 and the last three, each of which are diff --git a/doc/src/fix_store_force.txt b/doc/src/fix_store_force.txt index c988431f9d..93437c85b6 100644 --- a/doc/src/fix_store_force.txt +++ b/doc/src/fix_store_force.txt @@ -26,7 +26,7 @@ timestep when the fix is invoked, as described below. This is useful for storing forces before constraints or other boundary conditions are computed which modify the forces, so that unmodified forces can be "written to a dump file"_dump.html or accessed by other "output -commands"_Section_howto.html#howto_15 that use per-atom quantities. +commands"_Howto_output.html that use per-atom quantities. This fix is invoked at the point in the velocity-Verlet timestepping immediately after "pair"_pair_style.html, "bond"_bond_style.html, @@ -54,9 +54,9 @@ files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. This fix produces a per-atom array which can be accessed by various -"output commands"_Section_howto.html#howto_15. The number of columns -for each atom is 3, and the columns store the x,y,z forces on each -atom. The per-atom values be accessed on any timestep. +"output commands"_Howto_output.html. The number of columns for each +atom is 3, and the columns store the x,y,z forces on each atom. The +per-atom values be accessed on any timestep. No parameter of this fix can be used with the {start/stop} keywords of the "run"_run.html command. This fix is not invoked during "energy diff --git a/doc/src/fix_store_state.txt b/doc/src/fix_store_state.txt index df694fb97b..dee8070bbd 100644 --- a/doc/src/fix_store_state.txt +++ b/doc/src/fix_store_state.txt @@ -68,8 +68,7 @@ Define a fix that stores attributes for each atom in the group at the time the fix is defined. If {N} is 0, then the values are never updated, so this is a way of archiving an atom attribute at a given time for future use in a calculation or output. See the discussion of -"output commands"_Section_howto.html#howto_15 that take fixes as -inputs. +"output commands"_Howto_output.html that take fixes as inputs. If {N} is not zero, then the attributes will be updated every {N} steps. @@ -108,9 +107,8 @@ fix. If a single input is specified, this fix produces a per-atom vector. If multiple inputs are specified, a per-atom array is produced where the number of columns for each atom is the number of inputs. These -can be accessed by various "output -commands"_Section_howto.html#howto_15. The per-atom values be -accessed on any timestep. +can be accessed by various "output commands"_Howto_output.html. The +per-atom values be accessed on any timestep. No parameter of this fix can be used with the {start/stop} keywords of the "run"_run.html command. This fix is not invoked during "energy diff --git a/doc/src/fix_temp_berendsen.txt b/doc/src/fix_temp_berendsen.txt index 6944860e14..9092bbd30e 100644 --- a/doc/src/fix_temp_berendsen.txt +++ b/doc/src/fix_temp_berendsen.txt @@ -68,8 +68,8 @@ be used on atoms that also have their temperature controlled by another fix - e.g. by "fix nvt"_fix_nh.html or "fix langevin"_fix_langevin.html commands. -See "this howto section"_Section_howto.html#howto_16 of the manual for -a discussion of different ways to compute temperature and perform +See the "Howto thermostat"_Howto_thermostat.html doc page for a +discussion of different ways to compute temperature and perform thermostatting. This fix computes a temperature each timestep. To do this, the fix @@ -126,9 +126,9 @@ system's potential energy as part of "thermodynamic output"_thermo_style.html. This fix computes a global scalar which can be accessed by various -"output commands"_Section_howto.html#howto_15. The scalar is the -cumulative energy change due to this fix. The scalar value -calculated by this fix is "extensive". +"output commands"_Howto_output.html. The scalar is the cumulative +energy change due to this fix. The scalar value calculated by this +fix is "extensive". This fix can ramp its target temperature over multiple runs, using the {start} and {stop} keywords of the "run"_run.html command. See the diff --git a/doc/src/fix_temp_csvr.txt b/doc/src/fix_temp_csvr.txt index 4129ad73c8..6ce6ad7d9d 100644 --- a/doc/src/fix_temp_csvr.txt +++ b/doc/src/fix_temp_csvr.txt @@ -76,8 +76,8 @@ normally be used on atoms that also have their temperature controlled by another fix - e.g. by "fix nvt"_fix_nh.html or "fix langevin"_fix_langevin.html commands. -See "this howto section"_Section_howto.html#howto_16 of the manual for -a discussion of different ways to compute temperature and perform +See the "Howto thermostat"_Howto_thermostat.html doc page for a +discussion of different ways to compute temperature and perform thermostatting. These fixes compute a temperature each timestep. To do this, the fix @@ -135,9 +135,9 @@ the {start} and {stop} keywords of the "run"_run.html command. See the These fixes are not invoked during "energy minimization"_minimize.html. These fixes compute a global scalar which can be accessed by various -"output commands"_Section_howto.html#howto_15. The scalar is the -cumulative energy change due to the fix. The scalar value -calculated by this fix is "extensive". +"output commands"_Howto_output.html. The scalar is the cumulative +energy change due to the fix. The scalar value calculated by this fix +is "extensive". [Restrictions:] diff --git a/doc/src/fix_temp_rescale.txt b/doc/src/fix_temp_rescale.txt index eff25297c1..89f1777e36 100644 --- a/doc/src/fix_temp_rescale.txt +++ b/doc/src/fix_temp_rescale.txt @@ -75,8 +75,8 @@ be used on atoms that also have their temperature controlled by another fix - e.g. by "fix nvt"_fix_nh.html or "fix langevin"_fix_langevin.html commands. -See "this howto section"_Section_howto.html#howto_16 of the manual for -a discussion of different ways to compute temperature and perform +See the "Howto thermostat"_Howto_thermostat.html doc page for a +discussion of different ways to compute temperature and perform thermostatting. This fix computes a temperature each timestep. To do this, the fix @@ -133,9 +133,9 @@ system's potential energy as part of "thermodynamic output"_thermo_style.html. This fix computes a global scalar which can be accessed by various -"output commands"_Section_howto.html#howto_15. The scalar is the -cumulative energy change due to this fix. The scalar value -calculated by this fix is "extensive". +"output commands"_Howto_output.html. The scalar is the cumulative +energy change due to this fix. The scalar value calculated by this +fix is "extensive". This fix can ramp its target temperature over multiple runs, using the {start} and {stop} keywords of the "run"_run.html command. See the diff --git a/doc/src/fix_temp_rescale_eff.txt b/doc/src/fix_temp_rescale_eff.txt index f87c1a2192..8a79dc3275 100644 --- a/doc/src/fix_temp_rescale_eff.txt +++ b/doc/src/fix_temp_rescale_eff.txt @@ -51,9 +51,9 @@ system's potential energy as part of "thermodynamic output"_thermo_style.html. This fix computes a global scalar which can be accessed by various -"output commands"_Section_howto.html#howto_15. The scalar is the -cumulative energy change due to this fix. The scalar value -calculated by this fix is "extensive". +"output commands"_Howto_output.html. The scalar is the cumulative +energy change due to this fix. The scalar value calculated by this +fix is "extensive". This fix can ramp its target temperature over multiple runs, using the {start} and {stop} keywords of the "run"_run.html command. See the diff --git a/doc/src/fix_thermal_conductivity.txt b/doc/src/fix_thermal_conductivity.txt index 0353c095b2..2e10a89738 100644 --- a/doc/src/fix_thermal_conductivity.txt +++ b/doc/src/fix_thermal_conductivity.txt @@ -108,9 +108,9 @@ files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. This fix computes a global scalar which can be accessed by various -"output commands"_Section_howto.html#howto_15. The scalar is the -cumulative kinetic energy transferred between the bottom and middle -of the simulation box (in the {edim} direction) is stored as a scalar +"output commands"_Howto_output.html. The scalar is the cumulative +kinetic energy transferred between the bottom and middle of the +simulation box (in the {edim} direction) is stored as a scalar quantity by this fix. This quantity is zeroed when the fix is defined and accumulates thereafter, once every N steps. The units of the quantity are energy; see the "units"_units.html command for details. diff --git a/doc/src/fix_ti_spring.txt b/doc/src/fix_ti_spring.txt index 191f9e7c6b..b116d8e8a3 100644 --- a/doc/src/fix_ti_spring.txt +++ b/doc/src/fix_ti_spring.txt @@ -121,13 +121,12 @@ fix to add the energy stored in the per-atom springs to the system's potential energy as part of "thermodynamic output"_thermo_style.html. This fix computes a global scalar and a global vector quantities which -can be accessed by various "output -commands"_Section_howto.html#howto_15. The scalar is an energy which -is the sum of the spring energy for each atom, where the per-atom -energy is 0.5 * k * r^2. The vector has 2 positions, the first one is -the coupling parameter lambda and the second one is the time -derivative of lambda. The scalar and vector values calculated by this -fix are "extensive". +can be accessed by various "output commands"_Howto_output.html. The +scalar is an energy which is the sum of the spring energy for each +atom, where the per-atom energy is 0.5 * k * r^2. The vector has 2 +positions, the first one is the coupling parameter lambda and the +second one is the time derivative of lambda. The scalar and vector +values calculated by this fix are "extensive". No parameter of this fix can be used with the {start/stop} keywords of the "run"_run.html command. diff --git a/doc/src/fix_tmd.txt b/doc/src/fix_tmd.txt index 71d8d2c767..e1815e61d3 100644 --- a/doc/src/fix_tmd.txt +++ b/doc/src/fix_tmd.txt @@ -90,8 +90,7 @@ For more information about TMD, see "(Schlitter1)"_#Schlitter1 and No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. +by this fix for access by various "output commands"_Howto_output.html. This fix can ramp its rho parameter over multiple runs, using the {start} and {stop} keywords of the "run"_run.html command. See the diff --git a/doc/src/fix_ttm.txt b/doc/src/fix_ttm.txt index 48dfd254a0..d83118d427 100644 --- a/doc/src/fix_ttm.txt +++ b/doc/src/fix_ttm.txt @@ -272,18 +272,17 @@ None of the "fix_modify"_fix_modify.html options are relevant to these fixes. Both fixes compute 2 output quantities stored in a vector of length 2, -which can be accessed by various "output -commands"_Section_howto.html#howto_15. The first quantity is the -total energy of the electronic subsystem. The second quantity is the -energy transferred from the electronic to the atomic subsystem on that -timestep. Note that the velocity verlet integrator applies the fix ttm -forces to the atomic subsystem as two half-step velocity updates: one -on the current timestep and one on the subsequent timestep. -Consequently, the change in the atomic subsystem energy is lagged by -half a timestep relative to the change in the electronic subsystem -energy. As a result of this, users may notice slight fluctuations in -the sum of the atomic and electronic subsystem energies reported at -the end of the timestep. +which can be accessed by various "output commands"_Howto_output.html. +The first quantity is the total energy of the electronic +subsystem. The second quantity is the energy transferred from the +electronic to the atomic subsystem on that timestep. Note that the +velocity verlet integrator applies the fix ttm forces to the atomic +subsystem as two half-step velocity updates: one on the current +timestep and one on the subsequent timestep. Consequently, the change +in the atomic subsystem energy is lagged by half a timestep relative +to the change in the electronic subsystem energy. As a result of this, +users may notice slight fluctuations in the sum of the atomic and +electronic subsystem energies reported at the end of the timestep. The vector values calculated are "extensive". diff --git a/doc/src/fix_vector.txt b/doc/src/fix_vector.txt index 385d24cff1..69c999fd1a 100644 --- a/doc/src/fix_vector.txt +++ b/doc/src/fix_vector.txt @@ -37,7 +37,7 @@ simply store them. For a single specified value, the values are stored as a global vector of growing length. For multiple specified values, they are stored as rows in a global array, whose number of rows is growing. The resulting vector or array can be used by other -"output commands"_Section_howto.html#howto_15. +"output commands"_Howto_output.html. One way to to use this command is to accumulate a vector that is time-integrated using the "variable trap()"_variable.html function. @@ -127,9 +127,8 @@ files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. This fix produces a global vector or global array which can be -accessed by various "output commands"_Section_howto.html#howto_15. -The values can only be accessed on timesteps that are multiples of -{Nevery}. +accessed by various "output commands"_Howto_output.html. The values +can only be accessed on timesteps that are multiples of {Nevery}. A vector is produced if only a single input value is specified. An array is produced if multiple input values are specified. diff --git a/doc/src/fix_viscosity.txt b/doc/src/fix_viscosity.txt index f6603be624..8d73deb7c5 100644 --- a/doc/src/fix_viscosity.txt +++ b/doc/src/fix_viscosity.txt @@ -100,13 +100,12 @@ accurately infer a viscosity and should try increasing the Nevery parameter. An alternative method for calculating a viscosity is to run a NEMD -simulation, as described in "Section -6.13"_Section_howto.html#howto_13 of the manual. NEMD simulations -deform the simulation box via the "fix deform"_fix_deform.html -command. Thus they cannot be run on a charged system using a "PPPM -solver"_kspace_style.html since PPPM does not currently support -non-orthogonal boxes. Using fix viscosity keeps the box orthogonal; -thus it does not suffer from this limitation. +simulation, as described on the "Howto nemd"_Howto_nemd.html doc page. +NEMD simulations deform the simulation box via the "fix +deform"_fix_deform.html command. Thus they cannot be run on a charged +system using a "PPPM solver"_kspace_style.html since PPPM does not +currently support non-orthogonal boxes. Using fix viscosity keeps the +box orthogonal; thus it does not suffer from this limitation. [Restart, fix_modify, output, run start/stop, minimize info:] @@ -115,13 +114,13 @@ files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. This fix computes a global scalar which can be accessed by various -"output commands"_Section_howto.html#howto_15. The scalar is the -cumulative momentum transferred between the bottom and middle of the -simulation box (in the {pdim} direction) is stored as a scalar -quantity by this fix. This quantity is zeroed when the fix is defined -and accumulates thereafter, once every N steps. The units of the -quantity are momentum = mass*velocity. The scalar value calculated by -this fix is "intensive". +"output commands"_Howto_output.html. The scalar is the cumulative +momentum transferred between the bottom and middle of the simulation +box (in the {pdim} direction) is stored as a scalar quantity by this +fix. This quantity is zeroed when the fix is defined and accumulates +thereafter, once every N steps. The units of the quantity are +momentum = mass*velocity. The scalar value calculated by this fix is +"intensive". No parameter of this fix can be used with the {start/stop} keywords of the "run"_run.html command. This fix is not invoked during "energy diff --git a/doc/src/fix_viscous.txt b/doc/src/fix_viscous.txt index 9c30e40249..7ff517aec1 100644 --- a/doc/src/fix_viscous.txt +++ b/doc/src/fix_viscous.txt @@ -82,9 +82,9 @@ easily be used as a thermostat. No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. +by this fix for access by various "output commands"_Howto_output.html. +No parameter of this fix can be used with the {start/stop} keywords of +the "run"_run.html command. The "fix_modify"_fix_modify.html {respa} option is supported by this fix. This allows to set at which level of the "r-RESPA"_run_style.html diff --git a/doc/src/fix_wall.txt b/doc/src/fix_wall.txt index 959a103f02..fcd920934f 100644 --- a/doc/src/fix_wall.txt +++ b/doc/src/fix_wall.txt @@ -263,14 +263,14 @@ integrator the fix is adding its forces. Default is the outermost level. This fix computes a global scalar energy and a global vector of forces, which can be accessed by various "output -commands"_Section_howto.html#howto_15. Note that the scalar energy is -the sum of interactions with all defined walls. If you want the -energy on a per-wall basis, you need to use multiple fix wall -commands. The length of the vector is equal to the number of walls -defined by the fix. Each vector value is the normal force on a -specific wall. Note that an outward force on a wall will be a -negative value for {lo} walls and a positive value for {hi} walls. -The scalar and vector values calculated by this fix are "extensive". +commands"_Howto_output.html. Note that the scalar energy is the sum +of interactions with all defined walls. If you want the energy on a +per-wall basis, you need to use multiple fix wall commands. The +length of the vector is equal to the number of walls defined by the +fix. Each vector value is the normal force on a specific wall. Note +that an outward force on a wall will be a negative value for {lo} +walls and a positive value for {hi} walls. The scalar and vector +values calculated by this fix are "extensive". No parameter of this fix can be used with the {start/stop} keywords of the "run"_run.html command. diff --git a/doc/src/fix_wall_body_polygon.txt b/doc/src/fix_wall_body_polygon.txt index 4ba16b56c7..ebd25c2bbc 100644 --- a/doc/src/fix_wall_body_polygon.txt +++ b/doc/src/fix_wall_body_polygon.txt @@ -43,8 +43,8 @@ particles in the group interact with the wall when they are close enough to touch it. The nature of the interaction between the wall and the polygon particles is the same as that between the polygon particles themselves, which is similar to a Hookean potential. See -"Section 6.14"_Section_howto.html#howto_14 of the manual and the -"body"_body.html doc page for more details on using body particles. +the "Howto body"_Howto_body.html doc page for more details on using +body particles. The parameters {k_n}, {c_n}, {c_t} have the same meaning and units as those specified with the "pair_style @@ -83,9 +83,9 @@ to the derivative of this expression. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored by this fix for -access by various "output commands"_Section_howto.html#howto_15. No -parameter of this fix can be used with the {start/stop} keywords of -the "run"_run.html command. This fix is not invoked during "energy +access by various "output commands"_Howto_output.html. No parameter +of this fix can be used with the {start/stop} keywords of the +"run"_run.html command. This fix is not invoked during "energy minimization"_minimize.html. [Restrictions:] diff --git a/doc/src/fix_wall_body_polyhedron.txt b/doc/src/fix_wall_body_polyhedron.txt index c937cbdbbc..d3d8bc35a3 100644 --- a/doc/src/fix_wall_body_polyhedron.txt +++ b/doc/src/fix_wall_body_polyhedron.txt @@ -43,8 +43,8 @@ All particles in the group interact with the wall when they are close enough to touch it. The nature of the interaction between the wall and the polygon particles is the same as that between the polygon particles themselves, which is similar to a Hookean potential. See -"Section 6.14"_Section_howto.html#howto_14 of the manual and the -"body"_body.html doc page for more details on using body particles. +the "Howto body"_Howto_body.html doc page for more details on using +body particles. The parameters {k_n}, {c_n}, {c_t} have the same meaning and units as those specified with the "pair_style @@ -82,9 +82,9 @@ to the derivative of this expression. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored by this fix for -access by various "output commands"_Section_howto.html#howto_15. No -parameter of this fix can be used with the {start/stop} keywords of -the "run"_run.html command. This fix is not invoked during "energy +access by various "output commands"_Howto_output.html. No parameter +of this fix can be used with the {start/stop} keywords of the +"run"_run.html command. This fix is not invoked during "energy minimization"_minimize.html. [Restrictions:] diff --git a/doc/src/fix_wall_gran.txt b/doc/src/fix_wall_gran.txt index 5f1679604e..9796c39459 100644 --- a/doc/src/fix_wall_gran.txt +++ b/doc/src/fix_wall_gran.txt @@ -148,9 +148,9 @@ uninterrupted fashion. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored by this fix for -access by various "output commands"_Section_howto.html#howto_15. No -parameter of this fix can be used with the {start/stop} keywords of -the "run"_run.html command. This fix is not invoked during "energy +access by various "output commands"_Howto_output.html. No parameter +of this fix can be used with the {start/stop} keywords of the +"run"_run.html command. This fix is not invoked during "energy minimization"_minimize.html. [Restrictions:] diff --git a/doc/src/fix_wall_gran_region.txt b/doc/src/fix_wall_gran_region.txt index 92fb042194..908bcc3941 100644 --- a/doc/src/fix_wall_gran_region.txt +++ b/doc/src/fix_wall_gran_region.txt @@ -180,9 +180,9 @@ region with a different region ID. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored by this fix for -access by various "output commands"_Section_howto.html#howto_15. No -parameter of this fix can be used with the {start/stop} keywords of -the "run"_run.html command. This fix is not invoked during "energy +access by various "output commands"_Howto_output.html. No parameter +of this fix can be used with the {start/stop} keywords of the +"run"_run.html command. This fix is not invoked during "energy minimization"_minimize.html. [Restrictions:] diff --git a/doc/src/fix_wall_piston.txt b/doc/src/fix_wall_piston.txt index 4d7756c237..26018329eb 100644 --- a/doc/src/fix_wall_piston.txt +++ b/doc/src/fix_wall_piston.txt @@ -91,10 +91,10 @@ define the lattice spacings. No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. -This fix is not invoked during "energy minimization"_minimize.html. +by this fix for access by various "output commands"_Howto_output.html. +No parameter of this fix can be used with the {start/stop} keywords of +the "run"_run.html command. This fix is not invoked during "energy +minimization"_minimize.html. [Restrictions:] diff --git a/doc/src/fix_wall_reflect.txt b/doc/src/fix_wall_reflect.txt index 5380bdf738..2956046e20 100644 --- a/doc/src/fix_wall_reflect.txt +++ b/doc/src/fix_wall_reflect.txt @@ -154,10 +154,10 @@ instructions on how to use the accelerated styles effectively. No information about this fix is written to "binary restart files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. No global or per-atom quantities are stored -by this fix for access by various "output -commands"_Section_howto.html#howto_15. No parameter of this fix can -be used with the {start/stop} keywords of the "run"_run.html command. -This fix is not invoked during "energy minimization"_minimize.html. +by this fix for access by various "output commands"_Howto_output.html. +No parameter of this fix can be used with the {start/stop} keywords of +the "run"_run.html command. This fix is not invoked during "energy +minimization"_minimize.html. [Restrictions:] diff --git a/doc/src/fix_wall_region.txt b/doc/src/fix_wall_region.txt index 9700545dc9..8b3b3ff173 100644 --- a/doc/src/fix_wall_region.txt +++ b/doc/src/fix_wall_region.txt @@ -156,12 +156,11 @@ integrator the fix is adding its forces. Default is the outermost level. This fix computes a global scalar energy and a global 3-length vector of forces, which can be accessed by various "output -commands"_Section_howto.html#howto_15. The scalar energy is the sum -of energy interactions for all particles interacting with the wall -represented by the region surface. The 3 vector quantities are the -x,y,z components of the total force acting on the wall due to the -particles. The scalar and vector values calculated by this fix are -"extensive". +commands"_Howto_output.html. The scalar energy is the sum of energy +interactions for all particles interacting with the wall represented +by the region surface. The 3 vector quantities are the x,y,z +components of the total force acting on the wall due to the particles. +The scalar and vector values calculated by this fix are "extensive". No parameter of this fix can be used with the {start/stop} keywords of the "run"_run.html command. diff --git a/doc/src/fix_wall_srd.txt b/doc/src/fix_wall_srd.txt index c465896d37..3a8c2e41cd 100644 --- a/doc/src/fix_wall_srd.txt +++ b/doc/src/fix_wall_srd.txt @@ -166,9 +166,9 @@ files"_restart.html. None of the "fix_modify"_fix_modify.html options are relevant to this fix. This fix computes a global array of values which can be accessed by -various "output commands"_Section_howto.html#howto_15. The number of -rows in the array is equal to the number of walls defined by the fix. -The number of columns is 3, for the x,y,z components of force on each +various "output commands"_Howto_output.html. The number of rows in +the array is equal to the number of walls defined by the fix. The +number of columns is 3, for the x,y,z components of force on each wall. Note that an outward normal force on a wall will be a negative value diff --git a/doc/src/improper_umbrella.txt b/doc/src/improper_umbrella.txt index e72cc7f0ad..59fee0a664 100644 --- a/doc/src/improper_umbrella.txt +++ b/doc/src/improper_umbrella.txt @@ -22,7 +22,7 @@ improper_coeff 1 100.0 180.0 :pre The {umbrella} improper style uses the following potential, which is commonly referred to as a classic inversion and used in the -"DREIDING"_Section_howto.html#howto_4 force field: +"DREIDING"_Howto_bioFF.html force field: :c,image(Eqs/improper_umbrella.jpg) diff --git a/doc/src/kspace_modify.txt b/doc/src/kspace_modify.txt index 6d27bb7076..37c8c5b1d7 100644 --- a/doc/src/kspace_modify.txt +++ b/doc/src/kspace_modify.txt @@ -285,15 +285,15 @@ performance and accuracy in the results is obtained when these values are different. The {disp/auto} option controls whether the pppm/disp is allowed to -generate PPPM parameters automatically. If set to {no}, parameters have -to be specified using the {gewald/disp}, {mesh/disp}, -{force/disp/real} or {force/disp/kspace} keywords, or -the code will stop with an error message. When this option is set to -{yes}, the error message will not appear and the simulation will start. -For a typical application, using the automatic parameter generation -will provide simulations that are either inaccurate or slow. Using this -option is thus not recommended. For guidelines on how to obtain good -parameters, see the "How-To"_Section_howto.html#howto_24 discussion. +generate PPPM parameters automatically. If set to {no}, parameters +have to be specified using the {gewald/disp}, {mesh/disp}, +{force/disp/real} or {force/disp/kspace} keywords, or the code will +stop with an error message. When this option is set to {yes}, the +error message will not appear and the simulation will start. For a +typical application, using the automatic parameter generation will +provide simulations that are either inaccurate or slow. Using this +option is thus not recommended. For guidelines on how to obtain good +parameters, see the "Howto dispersion"_Howto_dispersion.html doc page. [Restrictions:] none diff --git a/doc/src/kspace_style.txt b/doc/src/kspace_style.txt index 8dbb3dde49..fa717b70ef 100644 --- a/doc/src/kspace_style.txt +++ b/doc/src/kspace_style.txt @@ -161,15 +161,16 @@ similar to the {ewald/disp} style. The 1/r^6 capability means that Lennard-Jones or Buckingham potentials can be used without a cutoff, i.e. they become full long-range potentials. -For these styles, you will possibly want to adjust the default choice of -parameters by using the "kspace_modify"_kspace_modify.html command. +For these styles, you will possibly want to adjust the default choice +of parameters by using the "kspace_modify"_kspace_modify.html command. This can be done by either choosing the Ewald and grid parameters, or by specifying separate accuracies for the real and kspace -calculations. When not making any settings, the simulation will stop with -an error message. Further information on the influence of the parameters -and how to choose them is described in "(Isele-Holder)"_#Isele-Holder2012, -"(Isele-Holder2)"_#Isele-Holder2013 and the -"How-To"_Section_howto.html#howto_24 discussion. +calculations. When not making any settings, the simulation will stop +with an error message. Further information on the influence of the +parameters and how to choose them is described in +"(Isele-Holder)"_#Isele-Holder2012, +"(Isele-Holder2)"_#Isele-Holder2013 and the "Howto +dispersion"_Howto_dispersion.html doc page. :line diff --git a/doc/src/lammps_tutorials.txt b/doc/src/lammps_tutorials.txt deleted file mode 100644 index 5ceda65b60..0000000000 --- a/doc/src/lammps_tutorials.txt +++ /dev/null @@ -1,6 +0,0 @@ - -Tutorials :h2 - -The following pages contain some in-depth tutorials for -selected topics, that did not fit into any other place -in the manual. diff --git a/doc/src/molecule.txt b/doc/src/molecule.txt index cd9ecce42c..b2ad547cf0 100644 --- a/doc/src/molecule.txt +++ b/doc/src/molecule.txt @@ -176,9 +176,8 @@ LAMMPS uses this info to properly exclude or weight bonded pairwise interactions between bonded atoms. See the "special_bonds"_special_bonds.html command for more details. One reason to list the special bond info explicitly is for the -"thermalized Drude oscillator model"_tutorial_drude.html which treats -the bonds between nuclear cores and Drude electrons in a different -manner. +"thermalized Drude oscillator model"_Howto_drude.html which treats the +bonds between nuclear cores and Drude electrons in a different manner. NOTE: Whether a section is required depends on how the molecule template is used by other LAMMPS commands. For example, to add a diff --git a/doc/src/neb.txt b/doc/src/neb.txt index 56f075c301..5c6053fca0 100644 --- a/doc/src/neb.txt +++ b/doc/src/neb.txt @@ -56,9 +56,8 @@ Note that if you have MPI installed, you can run a multi-replica simulation with more replicas (partitions) than you have physical processors, e.g you can run a 10-replica simulation on just one or two processors. You will simply not get the performance speed-up you -would see with one or more physical processors per replica. See -"Section 6.5"_Section_howto.html#howto_5 of the manual for further -discussion. +would see with one or more physical processors per replica. See the +"Howto replica"_Howto_replica.html doc page for further discussion. NOTE: As explained below, a NEB calculation perfoms a damped dynamics minimization across all the replicas. The minimizer uses whatever diff --git a/doc/src/pair_body_nparticle.txt b/doc/src/pair_body_nparticle.txt index 8c5b6e155d..78a9f2bb38 100644 --- a/doc/src/pair_body_nparticle.txt +++ b/doc/src/pair_body_nparticle.txt @@ -24,15 +24,14 @@ pair_coeff 1 1 1.0 1.5 2.5 :pre Style {body/nparticle} is for use with body particles and calculates pairwise body/body interactions as well as interactions between body -and point-particles. See "Section 6.14"_Section_howto.html#howto_14 -of the manual and the "body"_body.html doc page for more details on -using body particles. +and point-particles. See the "Howto body"_Howto_body.html doc page +for more details on using body particles. This pair style is designed for use with the "nparticle" body style, which is specified as an argument to the "atom-style body" command. -See the "body"_body.html doc page for more details about the body -styles LAMMPS supports. The "nparticle" style treats a body particle -as a rigid body composed of N sub-particles. +See the "Howto body"_Howto_body.html doc page for more details about +the body styles LAMMPS supports. The "nparticle" style treats a body +particle as a rigid body composed of N sub-particles. The coordinates of a body particle are its center-of-mass (COM). If the COMs of a pair of body particles are within the cutoff (global or diff --git a/doc/src/pair_body_rounded_polygon.txt b/doc/src/pair_body_rounded_polygon.txt index 9daeb08e9a..19807fbe39 100644 --- a/doc/src/pair_body_rounded_polygon.txt +++ b/doc/src/pair_body_rounded_polygon.txt @@ -29,9 +29,8 @@ pair_coeff 1 1 100.0 1.0 :pre Style {body/rounded/polygon} is for use with 2d models of body particles of style {rounded/polygon}. It calculates pairwise body/body interactions which can include body particles modeled as -1-vertex circular disks with a specified diameter. See "Section -6.14"_Section_howto.html#howto_14 of the manual and the -"body"_body.html doc page for more details on using body +1-vertex circular disks with a specified diameter. See the "Howto +body"_Howto_body.html doc page for more details on using body rounded/polygon particles. This pairwise interaction between rounded polygons is described in diff --git a/doc/src/pair_body_rounded_polyhedron.txt b/doc/src/pair_body_rounded_polyhedron.txt index dc559feaaf..d70a86f881 100644 --- a/doc/src/pair_body_rounded_polyhedron.txt +++ b/doc/src/pair_body_rounded_polyhedron.txt @@ -29,9 +29,8 @@ pair_coeff 1 1 100.0 1.0 :pre Style {body/rounded/polygon} is for use with 3d models of body particles of style {rounded/polyhedron}. It calculates pairwise body/body interactions which can include body particles modeled as -1-vertex spheres with a specified diameter. See "Section -6.14"_Section_howto.html#howto_14 of the manual and the -"body"_body.html doc page for more details on using body +1-vertex spheres with a specified diameter. See the "Howto +body"_Howto_body.html doc page for more details on using body rounded/polyhedron particles. This pairwise interaction between the rounded polyhedra is described diff --git a/doc/src/pair_born.txt b/doc/src/pair_born.txt index 2504fb7e25..143549cf2d 100644 --- a/doc/src/pair_born.txt +++ b/doc/src/pair_born.txt @@ -108,10 +108,10 @@ The {born/coul/dsf} style computes the Coulomb contribution with the damped shifted force model as in the "coul/dsf"_pair_coul.html style. Style {born/coul/long/cs} is identical to {born/coul/long} except that -a term is added for the "core/shell model"_Section_howto.html#howto_25 -to allow charges on core and shell particles to be separated by r = -0.0. The same correction is introduced for the {born/coul/dsf/cs} -style which is identical to {born/coul/dsf}. And likewise for +a term is added for the "core/shell model"_Howto_coreshell.html to +allow charges on core and shell particles to be separated by r = 0.0. +The same correction is introduced for the {born/coul/dsf/cs} style +which is identical to {born/coul/dsf}. And likewise for {born/coul/wolf/cs} style which is identical to {born/coul/wolf}. Note that these potentials are related to the "Buckingham diff --git a/doc/src/pair_buck.txt b/doc/src/pair_buck.txt index de247b9c01..2483a6c9e2 100644 --- a/doc/src/pair_buck.txt +++ b/doc/src/pair_buck.txt @@ -93,9 +93,8 @@ used as the cutoff for the A,C terms, and the second is the cutoff for the Coulombic term. Style {buck/coul/long/cs} is identical to {buck/coul/long} except that -a term is added for the "core/shell model"_Section_howto.html#howto_25 -to allow charges on core and shell particles to be separated by r = -0.0. +a term is added for the "core/shell model"_Howto_coreshell.html to +allow charges on core and shell particles to be separated by r = 0.0. Note that these potentials are related to the "Born-Mayer-Huggins potential"_pair_born.html. diff --git a/doc/src/pair_coul.txt b/doc/src/pair_coul.txt index 650575d055..e2bc78a2e6 100644 --- a/doc/src/pair_coul.txt +++ b/doc/src/pair_coul.txt @@ -205,9 +205,9 @@ pairwise interactions within this distance are computed directly; interactions outside that distance are computed in reciprocal space. Style {coul/long/cs} is identical to {coul/long} except that a term is -added for the "core/shell model"_Section_howto.html#howto_25 to allow -charges on core and shell particles to be separated by r = 0.0. The -same correction is introduced for the {coul/wolf/cs} style which is +added for the "core/shell model"_Howto_coreshell.html to allow charges +on core and shell particles to be separated by r = 0.0. The same +correction is introduced for the {coul/wolf/cs} style which is identical to {coul/wolf}. Styles {tip4p/cut} and {tip4p/long} implement the coulomb part of @@ -226,16 +226,16 @@ is to enable LAMMPS to "find" the 2 H atoms associated with each O atom. For example, if the atom ID of an O atom in a TIP4P water molecule is 500, then its 2 H atoms must have IDs 501 and 502. -See the "howto section"_Section_howto.html#howto_8 for more -information on how to use the TIP4P pair styles and lists of -parameters to set. Note that the neighbor list cutoff for Coulomb -interactions is effectively extended by a distance 2*qdist when using -the TIP4P pair style, to account for the offset distance of the -fictitious charges on O atoms in water molecules. Thus it is -typically best in an efficiency sense to use a LJ cutoff >= Coulomb -cutoff + 2*qdist, to shrink the size of the neighbor list. This leads -to slightly larger cost for the long-range calculation, so you can -test the trade-off for your model. +See the "Howto tip4p"_Howto_tip4p.html doc page for more information +on how to use the TIP4P pair styles and lists of parameters to set. +Note that the neighbor list cutoff for Coulomb interactions is +effectively extended by a distance 2*qdist when using the TIP4P pair +style, to account for the offset distance of the fictitious charges on +O atoms in water molecules. Thus it is typically best in an +efficiency sense to use a LJ cutoff >= Coulomb cutoff + 2*qdist, to +shrink the size of the neighbor list. This leads to slightly larger +cost for the long-range calculation, so you can test the trade-off for +your model. :line diff --git a/doc/src/pair_cs.txt b/doc/src/pair_cs.txt index c1084c6087..86eb02b0d7 100644 --- a/doc/src/pair_cs.txt +++ b/doc/src/pair_cs.txt @@ -54,8 +54,8 @@ pair_coeff 1 1 480.0 0.25 0.00 1.05 0.50 :pre These pair styles are designed to be used with the adiabatic core/shell model of "(Mitchell and Finchham)"_#MitchellFinchham2. See -"Section 6.25"_Section_howto.html#howto_25 of the manual for an -overview of the model as implemented in LAMMPS. +the "Howto coreshell"_Howto_coreshell.html doc page for an overview of +the model as implemented in LAMMPS. The styles with a {coul/long} term are identical to the "pair_style born/coul/long"_pair_born.html and "pair_style diff --git a/doc/src/pair_hbond_dreiding.txt b/doc/src/pair_hbond_dreiding.txt index 45f852c254..d641cb73ad 100644 --- a/doc/src/pair_hbond_dreiding.txt +++ b/doc/src/pair_hbond_dreiding.txt @@ -33,8 +33,8 @@ pair_coeff 1 2 hbond/dreiding/morse 3 i 3.88 1.7241379 2.9 2 9 11 90 :pre [Description:] The {hbond/dreiding} styles compute the Acceptor-Hydrogen-Donor (AHD) -3-body hydrogen bond interaction for the -"DREIDING"_Section_howto.html#howto_4 force field, given by: +3-body hydrogen bond interaction for the "DREIDING"_Howto_bioFF.html +force field, given by: :c,image(Eqs/pair_hbond_dreiding.jpg) @@ -65,8 +65,8 @@ potential for the Donor-Acceptor interactions. "(Liu)"_#Liu showed that the Morse form gives improved results for Dendrimer simulations, when n = 2. -See this "howto section"_Section_howto.html#howto_4 of the manual for -more information on the DREIDING forcefield. +See the "Howto bioFF"_Howto_bioFF.html doc page for more information +on the DREIDING forcefield. NOTE: Because the Dreiding hydrogen bond potential is only one portion of an overall force field which typically includes other pairwise diff --git a/doc/src/pair_lj.txt b/doc/src/pair_lj.txt index c2968ffdf3..a0f7effbb1 100644 --- a/doc/src/pair_lj.txt +++ b/doc/src/pair_lj.txt @@ -185,9 +185,9 @@ distance are computed directly; interactions outside that distance are computed in reciprocal space. Style {lj/cut/coul/long/cs} is identical to {lj/cut/coul/long} except -that a term is added for the "core/shell -model"_Section_howto.html#howto_25 to allow charges on core and shell -particles to be separated by r = 0.0. +that a term is added for the "core/shell model"_Howto_coreshell.html +to allow charges on core and shell particles to be separated by r = +0.0. Style {coul/wolf} adds a Coulombic pairwise interaction via the Wolf summation method, described in "Wolf"_#Wolf1, given by: @@ -223,16 +223,16 @@ is to enable LAMMPS to "find" the 2 H atoms associated with each O atom. For example, if the atom ID of an O atom in a TIP4P water molecule is 500, then its 2 H atoms must have IDs 501 and 502. -See the "howto section"_Section_howto.html#howto_8 for more -information on how to use the TIP4P pair styles and lists of -parameters to set. Note that the neighbor list cutoff for Coulomb -interactions is effectively extended by a distance 2*qdist when using -the TIP4P pair style, to account for the offset distance of the -fictitious charges on O atoms in water molecules. Thus it is -typically best in an efficiency sense to use a LJ cutoff >= Coulomb -cutoff + 2*qdist, to shrink the size of the neighbor list. This leads -to slightly larger cost for the long-range calculation, so you can -test the trade-off for your model. +See the "Howto tip4p"_Howto_tip4p.html doc page for more information +on how to use the TIP4P pair styles and lists of parameters to set. +Note that the neighbor list cutoff for Coulomb interactions is +effectively extended by a distance 2*qdist when using the TIP4P pair +style, to account for the offset distance of the fictitious charges on +O atoms in water molecules. Thus it is typically best in an +efficiency sense to use a LJ cutoff >= Coulomb cutoff + 2*qdist, to +shrink the size of the neighbor list. This leads to slightly larger +cost for the long-range calculation, so you can test the trade-off for +your model. For all of the {lj/cut} pair styles, the following coefficients must be defined for each pair of atoms types via the diff --git a/doc/src/pair_lj_long.txt b/doc/src/pair_lj_long.txt index bc851adb74..0dd55b7e32 100644 --- a/doc/src/pair_lj_long.txt +++ b/doc/src/pair_lj_long.txt @@ -90,7 +90,7 @@ is to enable LAMMPS to "find" the 2 H atoms associated with each O atom. For example, if the atom ID of an O atom in a TIP4P water molecule is 500, then its 2 H atoms must have IDs 501 and 502. -See the "howto section"_Section_howto.html#howto_8 for more +See the the "Howto tip4p"_Howto_tip4p.html doc page for more information on how to use the TIP4P pair style. Note that the neighbor list cutoff for Coulomb interactions is effectively extended by a distance 2*qdist when using the TIP4P pair style, to account for diff --git a/doc/src/pair_thole.txt b/doc/src/pair_thole.txt index 11d4b85cff..42c58e9882 100644 --- a/doc/src/pair_thole.txt +++ b/doc/src/pair_thole.txt @@ -45,8 +45,8 @@ pair_style lj/cut/thole/long 2.6 12.0 :pre The {thole} pair styles are meant to be used with force fields that include explicit polarization through Drude dipoles. This link describes how to use the "thermalized Drude oscillator -model"_tutorial_drude.html in LAMMPS and polarizable models in LAMMPS -are discussed in "this Section"_Section_howto.html#howto_25. +model"_Howto_drude.html in LAMMPS and polarizable models in LAMMPS are +discussed on the "Howto polarizable"_Howto_polarizable.html doc page. The {thole} pair style should be used as a sub-style within in the "pair_hybrid/overlay"_pair_hybrid.html command, in conjunction with a diff --git a/doc/src/prd.txt b/doc/src/prd.txt index 3c0305e316..f298d83385 100644 --- a/doc/src/prd.txt +++ b/doc/src/prd.txt @@ -69,8 +69,8 @@ simulation with more replicas (partitions) than you have physical processors, e.g you can run a 10-replica simulation on one or two processors. However for PRD, this makes little sense, since running a replica on virtual instead of physical processors,offers no effective -parallel speed-up in searching for infrequent events. See "Section -6.5"_Section_howto.html#howto_5 of the manual for further discussion. +parallel speed-up in searching for infrequent events. See the "Howto +replica"_Howto_replica.html doc page for further discussion. When a PRD simulation is performed, it is assumed that each replica is running the same model, though LAMMPS does not check for this. diff --git a/doc/src/read_data.txt b/doc/src/read_data.txt index fd297e36c1..4f6a3988b9 100644 --- a/doc/src/read_data.txt +++ b/doc/src/read_data.txt @@ -322,9 +322,9 @@ with tilt factors that exceed these limits, you can use the "box tilt"_box.html command, with a setting of {large}; a setting of {small} is the default. -See "Section 6.12"_Section_howto.html#howto_12 of the doc pages -for a geometric description of triclinic boxes, as defined by LAMMPS, -and how to transform these parameters to and from other commonly used +See the "Howto triclinic"_Howto_triclinic.html doc page for a +geometric description of triclinic boxes, as defined by LAMMPS, and +how to transform these parameters to and from other commonly used triclinic representations. When a triclinic system is used, the simulation domain should normally @@ -772,9 +772,9 @@ the "bodies" keyword. Each body can have a variable number of integer and/or floating-point values. The number and meaning of the values is defined by the body -style, as described in the "body"_body.html doc page. The body style -is given as an argument to the "atom_style body"_atom_style.html -command. +style, as described in the "Howto body"_Howto_body.html doc page. The +body style is given as an argument to the "atom_style +body"_atom_style.html command. The Ninteger and Ndouble values determine how many integer and floating-point values are specified for this particle. Ninteger and diff --git a/doc/src/region.txt b/doc/src/region.txt index 1ac3861e67..b32c09ed6f 100644 --- a/doc/src/region.txt +++ b/doc/src/region.txt @@ -186,9 +186,9 @@ functions, and include "thermo_style"_thermo_style.html command keywords for the simulation box parameters and timestep and elapsed time. Thus it is easy to specify a time-dependent radius. -See "Section 6.12"_Section_howto.html#howto_12 of the doc pages -for a geometric description of triclinic boxes, as defined by LAMMPS, -and how to transform these parameters to and from other commonly used +See the "Howto tricilinc"_Howto_triclinic.html doc page for a +geometric description of triclinic boxes, as defined by LAMMPS, and +how to transform these parameters to and from other commonly used triclinic representations. The {union} style creates a region consisting of the volume of all the diff --git a/doc/src/run.txt b/doc/src/run.txt index 913d81bb4d..02860c0b97 100644 --- a/doc/src/run.txt +++ b/doc/src/run.txt @@ -127,9 +127,9 @@ be redefined, e.g. to reset a thermostat temperature. Or this could be useful for invoking a command you have added to LAMMPS that wraps some other code (e.g. as a library) to perform a computation periodically during a long LAMMPS run. See the "Modify"_Modify.html -doc page for info about how to add new commands to LAMMPS. See "this -section"_Section_howto.html#howto_10 of the documentation for ideas -about how to couple LAMMPS to other codes. +doc page for info about how to add new commands to LAMMPS. See the +"Howto couple"_Howto_couple.html doc page for ideas about how to +couple LAMMPS to other codes. With the {every} option, N total steps are simulated, in shorter runs of M steps each. After each M-length run, the specified commands are diff --git a/doc/src/tad.txt b/doc/src/tad.txt index f5e7c6d653..9ffa24d012 100644 --- a/doc/src/tad.txt +++ b/doc/src/tad.txt @@ -92,9 +92,8 @@ restricts you to having exactly one processor per replica. For more information, see the documentation for the "neb"_neb.html command. In the current LAMMPS implementation of TAD, all the non-NEB TAD operations are performed on the first partition, while the other -partitions remain idle. See "Section -6.5"_Section_howto.html#howto_5 of the manual for further discussion of -multi-replica simulations. +partitions remain idle. See the "Howto replica"_Howto_replica.html doc +page for further discussion of multi-replica simulations. A TAD run has several stages, which are repeated each time an event is performed. The logic for a TAD run is as follows: diff --git a/doc/src/temper.txt b/doc/src/temper.txt index b1c47c8076..e65f59ebed 100644 --- a/doc/src/temper.txt +++ b/doc/src/temper.txt @@ -32,14 +32,13 @@ replicas (ensembles) of a system. Two or more replicas must be used. Each replica runs on a partition of one or more processors. Processor partitions are defined at run-time using the -partition command-line -switch; see "Section 2.6"_Section_start.html#start_6 of the -manual. Note that if you have MPI installed, you can run a -multi-replica simulation with more replicas (partitions) than you have -physical processors, e.g you can run a 10-replica simulation on one or -two processors. You will simply not get the performance speed-up you -would see with one or more physical processors per replica. See "this -section"_Section_howto.html#howto_5 of the manual for further -discussion. +switch; see "Section 2.6"_Section_start.html#start_6 of the manual. +Note that if you have MPI installed, you can run a multi-replica +simulation with more replicas (partitions) than you have physical +processors, e.g you can run a 10-replica simulation on one or two +processors. You will simply not get the performance speed-up you +would see with one or more physical processors per replica. See the +"Howto replica"_Howto_replica.html doc page for further discussion. Each replica's temperature is controlled at a different value by a fix with {fix-ID} that controls temperature. Most thermostat fix styles diff --git a/doc/src/thermo_style.txt b/doc/src/thermo_style.txt index 18c5ad5ba1..64e0785586 100644 --- a/doc/src/thermo_style.txt +++ b/doc/src/thermo_style.txt @@ -286,11 +286,11 @@ takes place. The keywords {cella}, {cellb}, {cellc}, {cellalpha}, {cellbeta}, {cellgamma}, correspond to the usual crystallographic quantities that -define the periodic unit cell of a crystal. See "this -section"_Section_howto.html#howto_12 of the doc pages for a geometric -description of triclinic periodic cells, including a precise definition -of these quantities in terms of the internal LAMMPS cell dimensions -{lx}, {ly}, {lz}, {yz}, {xz}, {xy}. +define the periodic unit cell of a crystal. See the "Howto +triclinic"_Howto_triclinic.html doc page for a geometric description +of triclinic periodic cells, including a precise definition of these +quantities in terms of the internal LAMMPS cell dimensions {lx}, {ly}, +{lz}, {yz}, {xz}, {xy}. :line diff --git a/doc/src/tutorials.txt b/doc/src/tutorials.txt deleted file mode 100644 index 338439ac8e..0000000000 --- a/doc/src/tutorials.txt +++ /dev/null @@ -1,15 +0,0 @@ -Tutorials :h1 - - diff --git a/doc/src/velocity.txt b/doc/src/velocity.txt index b8299a5acf..057f0054be 100644 --- a/doc/src/velocity.txt +++ b/doc/src/velocity.txt @@ -139,10 +139,9 @@ if rot = yes, the angular momentum is zeroed. If specified, the {temp} keyword is used by {create} and {scale} to specify a "compute"_compute.html that calculates temperature in a desired way, e.g. by first subtracting out a velocity bias, as -discussed in "Section 6.16"_Section_howto.html#howto_16 of the doc -pages. If this keyword is not specified, {create} and {scale} -calculate temperature using a compute that is defined internally as -follows: +discussed on the "Howto thermostat"_Howto_thermostat.html doc page. +If this keyword is not specified, {create} and {scale} calculate +temperature using a compute that is defined internally as follows: compute velocity_temp group-ID temp :pre @@ -161,11 +160,11 @@ The {bias} keyword with a {yes} setting is used by {create} and If the temperature compute also calculates a velocity bias, the the bias is subtracted from atom velocities before the {create} and {scale} operations are performed. After the operations, the bias is -added back to the atom velocities. See "Section -6.16"_Section_howto.html#howto_16 of the doc pages for more discussion -of temperature computes with biases. Note that the velocity bias is -only applied to atoms in the temperature compute specified with the -{temp} keyword. +added back to the atom velocities. See the "Howto +thermostat"_Howto_thermostat.html doc page for more discussion of +temperature computes with biases. Note that the velocity bias is only +applied to atoms in the temperature compute specified with the {temp} +keyword. As an example, assume atoms are currently streaming in a flow direction (which could be separately initialized with the {ramp}