"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

communicate command :h3

[Syntax:]

communicate style keyword value ... :pre

style = {single} or {multi} :ulb,l
zero or more keyword/value pairs may be appended :l
keyword = {group} :l
  {group} value = group-ID = only communicate atoms in the group :pre
:ule

[Examples:]

communicate multi
communicate multi group solvent :pre

[Description:]

This command sets the style of inter-processor communication that
occurs each timestep as atom coordinates and other properties are
exchanged between neighboring processors and stored as properties of
ghost atoms.

The default style is {single} which means each processor acquires
information for ghost atoms that are within a single distance from its
sub-domain.  The distance is the maximum of the neighbor cutoff for
all atom type pairs.

For many systems this is an efficient algorithm, but for systems with
widely varying cutoffs for different type pairs, the {multi} style can
be faster.  In this case, each atom type is assigned its own distance
cutoff for communication purposes, and fewer atoms will be
communicated.  See the "neighbor multi"_neighbor.html command for a
neighbor list construction option that may also be beneficial for
simulations of this kind.

The {group} option will limit communication to atoms in the specified
group.  This can be useful for models where no ghost atoms are needed
for some kinds of particles.  All atoms (not just those in the
specified group) will still migrate to new processors as they move.
The group specified with this option must also be specified via the
"atom_modify first" command.

[Restrictions:] none

[Related commands:]

"neighbor"_neighbor.html

[Default:]

The default settings are style = single and group = all.