lammps/doc/change_box.txt

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"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
change_box command :h3
[Syntax:]
change_box style :pre
style = {ortho} or {triclinic} :l
{ortho} = convert simulation box from non-orthogonal (triclinic) to orthogonal
{triclinic} = convert simulation box from orthogonal to non-orthogonal (triclinic) :pre
[Examples:]
change_box ortho
change_box triclinic :pre
[Description:]
By default LAMMPS runs a simulation in an orthogonal, axis-aligned
simulation box. LAMMPS can also run simulations in "non-orthogonal
(triclinic) simulation boxes"_Section_howto.html#4_12. A box is
defined as either orthogonal or non-orthogonal when it is created via
the "create_box"_create_box.html, "read_data"_read_data.html, or
"read_restart"_read_restart.html commands.
This command allows you to toggle the existing simulation box from
orthogonal to non-orthogonal and vice versa. For example, an initial
equilibration simulation can be run in an orthogonal box, the box can
be toggled to non-orthogonal, and then a "non-equilibrium MD (NEMD)
simulation"_Section_howto.html#4_13 can be run with deformation via
the "fix deform"_fix_deform.html command.
Note that if the simulation box is currently non-orthogonal and has
non-zero tilt in xy, yz, or xz, then it cannot be converted to an
orthogonal box.
[Restrictions:]
At the point in the input script when this command is issued, no
"dumps"_dump.html can be active, nor can a "fix
ave/spatial"_fix_ave_spatial.html or "fix deform"_fix_deform.html be
active. This is because these commands test whether the simulation
box is orthogonal when they are first issued. Note that these
commands can appear in your script before a change_box command is
issued, so long as an "undump"_undump.html or "unfix"_unfix.html
command is also used to turn them off.
[Related commands:] none
[Default:] none