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pair_style morse command

pair_style morse/opt command

Syntax:

pair_style morse cutoff 

Examples:

pair_style morse 2.5
pair_style morse/opt 2.5
pair_coeff * * 100.0 2.0 1.5
pair_coeff 1 1 100.0 2.0 1.5 3.0 

Description:

Style morse computes pairwise interactions with the formula

Rc is the cutoff.

The following coefficients must be defined for each pair of atoms 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 morse cutoff is used.

Style morse/opt is an optimized version of style morse that should give identical answers. Depending on system size and the processor you are running on, it may be 5-25% faster (for the pairwise portion of the run time).


Mixing, shift, table, tail correction, per-atom energy/stress, restart, rRESPA info:

None of the Morse pair styles support mixing. Thus, coefficients for all I,J pairs must be specified explicitly.

All of the Morse pair styles support the pair_modify shift option for the energy of the pair interaction.

The pair_modify table options is not relevant for the Morse pair styles.

None of the Morse pair styles support the pair_modify tail option for adding long-range tail corrections to energy and pressure.

All of the Morse pair styles can calculate per-atom energy and stress, as used by the compute epair/atom, compute stress/atom, and dump custom commands.

All of the Morse pair styles write their 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.


Restrictions:

The morse/opt style is part of the "opt" package. It is only enabled if LAMMPS was built with that package. See the Making LAMMPS section for more info.

Related commands:

pair_coeff

Default: none