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pair_style gauss command

pair_style gauss/omp command

Syntax:

pair_style gauss cutoff 

Examples:

pair_style gauss 12.0 
pair_coeff * * 1.0 0.9
pair_coeff 1 4 1.0 0.9 10.0 

Description:

Style gauss computes a tethering potential of the form

between an atom and its corresponding tether site which will typically be a frozen atom in the simulation. Rc is the cutoff.

The following coefficients must be defined for each pair of atom types via the pair_coeff command as in the examples above, or in the data file or restart files read by the read_data or read_restart commands:

The last coefficient is optional. If not specified, the global cutoff is used.


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 this section 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 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 when you invoke LAMMPS, or you can use the suffix command in your input script.

See this section of the manual for more instructions on how to use the accelerated styles effectively.


Mixing, shift, table, tail correction, restart, rRESPA info:

This pair style does not support mixing. Thus, coefficients for all I,J pairs must be specified explicitly.

This pair style does not support the pair_modify shift option. There is no effect due to the Gaussian well beyond the cutoff; hence reasonable cutoffs need to be specified.

The pair_modify table and tail options are not relevant for this pair style.

This pair style does not support the pair_modify table option, since a tabulation capability does not exist for this potential.

This pair style writes its information to binary restart files, 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 command. It does not support the inner, middle, outer keywords.

This pair style tallies an "occupancy" count of how many Gaussian-well sites have an atom within the distance at which the force is a maximum = sqrt(0.5/b). This quantity can be accessed via the compute pair command as a vector of values of length 1.

To print this quantity to the log file (with a descriptive column heading) the following commands could be included in an input script:

compute gauss all pair gauss
variable occ equal c_gauss[1]
thermo_style custom step temp epair v_occ 

Restrictions: none

Related commands:

pair_coeff

Default: none