# pair_style lj96/cut command

Accelerator Variants: *lj96/cut/gpu*, *lj96/cut/omp*

## Syntax

``` LAMMPS
pair_style lj96/cut cutoff
```

-   cutoff = global cutoff for lj96/cut interactions (distance units)

## Examples

``` LAMMPS
pair_style lj96/cut 2.5
pair_coeff * * 1.0 1.0 4.0
pair_coeff 1 1 1.0 1.0
```

## Description

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

$$E = 4 \epsilon \left[ \left(\frac{\sigma}{r}\right)^{9} -
\left(\frac{\sigma}{r}\right)^6 \right]
                    \qquad r < r_c$$

$r_c$ is the cutoff.

The following coefficients must be defined for each pair of atoms types
via the [pair_coeff](pair_coeff) command as in the examples above, or in
the data file or restart files read by the [read_data](read_data) or
[read_restart](read_restart) commands, or by mixing as described below:

-   $\epsilon$ (energy units)
-   $\sigma$ (distance units)
-   cutoff (distance units)

The last coefficient is optional. If not specified, the global LJ cutoff
specified in the pair_style command is used.

------------------------------------------------------------------------

Styles with a *gpu*, *intel*, *kk*, *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 on the [Accelerator packages](Speed_packages)
page. 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 GPU, INTEL, KOKKOS, OPENMP, and
OPT packages, respectively. They are only enabled if LAMMPS was built
with those packages. See the [Build package](Build_package) page 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](Run_options) when you invoke LAMMPS, or you can use the
[suffix](suffix) command in your input script.

See the [Accelerator packages](Speed_packages) page for more
instructions on how to use the accelerated styles effectively.

------------------------------------------------------------------------

## 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) shift option for
the energy of the pair interaction.

The [pair_modify](pair_modify) table option is not relevant for this
pair style.

This pair style supports the [pair_modify](pair_modify) 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), 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) command, meaning the
pairwise forces can be partitioned by distance at different levels of
the rRESPA hierarchy. See the [run_style](run_style) command for
details.

------------------------------------------------------------------------

## Restrictions

This pair style is part of the EXTRA-PAIR package. It is only enabled if
LAMMPS was built with that package. See the [Build
package](Build_package) page for more info.

## Related commands

[pair_coeff](pair_coeff)

## Default

none