"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 lj96/cut command :h3
pair_style lj96/cut/gpu command :h3

[Syntax:]

pair_style style cutoff :pre

style = {lj96/cut} or {lj96/cut/gpu}
cutoff = global cutoff for lj96/cut interactions (distance units) :ul

[Examples:]

pair_style lj96/cut 2.5
pair_style lj96/cut/gpu 2.5
pair_coeff * * 1.0 1.0 4.0
pair_coeff 1 1 1.0 1.0 :pre

[Description:]

The {lj96/cut} style compute a 9/6 Lennard-Jones potential, instead
of the standard 12/6 potential, given by

:c,image(Eqs/pair_lj96.jpg)

Rc is the cutoff.

Style {lj96/cut/gpu} is a GPU-enabled version of style {lj96/cut}.
See more details below.

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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The {lj96/cut/gpu} style is identical to the {lj96/cut} style, except that
each processor off-loads its pairwise calculations to a 
GPU chip. Depending on the hardware available on your system this can provide a
speed-up.  See the "Running on GPUs"_Section_start.html#2_8 section of
the manual for more details about hardware and software requirements
for using GPUs.

More details about these settings and various possible hardware
configuration are in "this section"_Section_start.html#2_8 of the
manual.

Additional requirements in your input script to run with the {lj96/cut/gpu} 
style are as follows:

The "newton pair"_newton.html setting must be {off} and
"fix gpu"_fix_gpu.html must be used. The fix controls the
essential GPU selection and initialization steps

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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 all of the lj/cut pair styles can be mixed.
The default mix value is {geometric}.  See the "pair_modify" command
for details.

This pair style supports the "pair_modify"_pair_modify.html shift
option for the energy of the pair interaction.

The "pair_modify"_pair_modify.html table option is not relevant
for this pair style.

This pair style supports the "pair_modify"_pair_modify.html tail
option for adding a long-range tail correction to the energy and
pressure of the pair interaction.

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 supports the use of the {inner}, {middle}, and {outer}
keywords of the "run_style respa"_run_style.html command, meaning the
pairwise forces can be partitioned by distance at different levels of
the rRESPA hierarchy.  See the "run_style"_run_style.html command for
details.

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[Restrictions:]

The {lj96/cut/gpu} style is part of the "gpu" package. It
is only enabled if LAMMPS is built with this packages.  See the
"Making LAMMPS"_Section_start.html#2_3 section for more info.

[Related commands:]

"pair_coeff"_pair_coeff.html

[Default:] none
