lammps/doc/pair_lj_sf.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)
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pair_style lj/sf command :h3
pair_style lj/sf/omp command :h3
[Syntax:]
pair_style lj/sf cutoff :pre
cutoff = global cutoff for Lennard-Jones interactions (distance units) :ul
[Examples:]
pair_style lj/sf 2.5
pair_coeff * * 1.0 1.0
pair_coeff 1 1 1.0 1.0 3.0 :pre
[Description:]
Style {lj/sf} computes a truncated and force-shifted LJ interaction
(Shifted Force Lennard-Jones), so that both the potential and the
force go continuously to zero at the cutoff "(Toxvaerd)"_#Toxvaerd:
:c,image(Eqs/pair_lj_sf.jpg)
The following coefficients must be defined for each pair of atoms
types via the "pair_coeff"_pair_coeff.html command as in the examples
above, or in the data file or restart files read by the
"read_data"_read_data.html or "read_restart"_read_restart.html
commands, or by mixing as described below:
epsilon (energy units)
sigma (distance units)
cutoff (distance units) :ul
The last coefficient is optional. If not specified, the global
LJ cutoff specified in the pair_style command is used.
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Styles with a {cuda}, {gpu}, {omp}, or {opt} suffix are functionally
the same as the corresponding style without the suffix. They have
been optimized to run faster, depending on your available hardware, as
discussed in "Section_accelerate"_Section_accelerate.html of the
manual. The accelerated styles take the same arguments and should
produce the same results, except for round-off and precision issues.
These accelerated styles are part of the USER-CUDA, GPU, USER-OMP and OPT
packages, respectively. They are only enabled if LAMMPS was built with
those packages. See the "Making LAMMPS"_Section_start.html#start_3
section for more info.
You can specify the accelerated styles explicitly in your input script
by including their suffix, or you can use the "-suffix command-line
switch"_Section_start.html#start_7 when you invoke LAMMPS, or you can
use the "suffix"_suffix.html command in your input script.
See "Section_accelerate"_Section_accelerate.html of the manual for
more instructions on how to use the accelerated styles effectively.
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[Mixing, shift, table, tail correction, restart, rRESPA info]:
For atom type pairs I,J and I != J, the epsilon and sigma
coefficients and cutoff distance for this pair style can be mixed.
Rin is a cutoff value and is mixed like the cutoff. The
default mix value is {geometric}. See the "pair_modify" command for
details.
The "pair_modify"_pair_modify.html shift option is not relevant for
this pair style, since the pair interaction goes to 0.0 at the cutoff.
The "pair_modify"_pair_modify.html table option is not relevant
for this pair style.
This pair style does not support the "pair_modify"_pair_modify.html
tail option for adding long-range tail corrections to energy and
pressure, since the energy of the pair interaction is smoothed to 0.0
at the cutoff.
This pair style writes its information to "binary restart
files"_restart.html, so pair_style and pair_coeff commands do not need
to be specified in an input script that reads a restart file.
This pair style can only be used via the {pair} keyword of the
"run_style respa"_run_style.html command. It does not support the
{inner}, {middle}, {outer} keywords.
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[Restrictions:]
This pair style is part of the USER-MISC package. It is only enabled
if LAMMPS was built with that package. See the "Making
LAMMPS"_Section_start.html#start_3 section for more info.
[Related commands:]
"pair_coeff"_pair_coeff.html
[Default:] none
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:link(Toxvaerd)
[(Toxvaerd)] Toxvaerd, Dyre, J Chem Phys, 134, 081102 (2011).