lammps/doc/pair_morse.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)
:line
pair_style morse command :h3
pair_style morse/opt command :h3
[Syntax:]
pair_style morse cutoff :pre
cutoff = global cutoff for Morse interactions (distance units) :ul
[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 :pre
[Description:]
Style {morse} computes pairwise interactions with the formula
:c,image(Eqs/pair_morse.jpg)
Rc is the cutoff.
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:
D0 (energy units)
alpha (1/distance units)
r0 (distance units)
cutoff (distance units) :ul
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).
[Restrictions:]
The {morse} potential does not support the
"pair_modify"_pair_modify.hmtl {mix} option. Coefficients for all i,j
pairs must be specified explicitly.
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_start.html#2_3 section for more info.
[Related commands:]
"pair_coeff"_pair_coeff.html
[Default:] none