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
[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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[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).