forked from lijiext/lammps
92 lines
2.6 KiB
Plaintext
92 lines
2.6 KiB
Plaintext
"LAMMPS WWW Site"_lws - "LAMMPS Documentation"_ld - "LAMMPS Commands"_lc :c
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:link(lws,http://lammps.sandia.gov)
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:link(ld,Manual.html)
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:link(lc,Section_commands.html#comm)
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:line
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pair_style gauss command :h3
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[Syntax:]
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pair_style gauss cutoff :pre
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cutoff = global cutoff for Gauss interactions (distance units) :ul
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[Examples:]
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pair_style gauss 12.0
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pair_coeff * * 1.0 0.9
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pair_coeff 1 4 1.0 0.9 10.0 :pre
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[Description:]
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Style {gauss} computes a tethering potential of the form
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:c,image(Eqs/pair_gauss.jpg)
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between an atom and its corresponding tether site which will typically
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be a frozen atom in the simulation. Rc is the cutoff.
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The following coefficients must be defined for each pair of atom types
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via the "pair_coeff"_pair_coeff.html command as in the examples above,
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or in the data file or restart files read by the
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"read_data"_read_data.html or "read_restart"_read_restart.html
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commands:
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A (energy units)
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B (1/distance^2 units)
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cutoff (distance units) :ul
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The last coefficient is optional. If not specified, the global cutoff
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is used.
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:line
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[Mixing, shift, table, tail correction, restart, rRESPA info]:
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This pair style does not support mixing. Thus, coefficients for all
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I,J pairs must be specified explicitly.
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This pair style does not support the "pair_modify"_pair_modify.html
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shift option. There is no effect due to the Gaussian well beyond the
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cutoff; hence reasonable cutoffs need to be specified.
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The "pair_modify"_pair_modify.html table and tail options are not
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relevant for this pair style.
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This pair style does not support the "pair_modify"_pair_modify.html
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table option, since a tabulation capability does not exist for this
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potential.
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This pair style writes its information to "binary restart
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files"_restart.html, so pair_style and pair_coeff commands do not need
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to be specified in an input script that reads a restart file.
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This pair style can only be used via the {pair} keyword of the
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"run_style respa"_run_style.html command. It does not support the
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{inner}, {middle}, {outer} keywords.
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This pair style tallies an "occupancy" count of how many Gaussian-well
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sites have an atom within the distance at which the force is a maximum
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= sqrt(0.5/b). This quantity can be accessed via the "compute
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pair"_compute_pair.html command as a vector of values of length 1.
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To print this quantity to the log file (with a descriptive column
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heading) the following commands could be included in an input script:
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compute gauss all pair gauss
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variable occ equal c_gauss\[1\]
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thermo_style custom step temp epair v_occ :pre
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:line
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[Restrictions:] none
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[Related commands:]
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"pair_coeff"_pair_coeff.html
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[Default:] none
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