lammps/doc/pair_zero.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 zero command :h3
[Syntax:]
pair_style zero cutoff {nocoeff} :pre
zero = style name of this pair style
cutoff = global cutoff (distance units)
nocoeff = ignore all pair_coeff parameters (optional) :l
[Examples:]
pair_style zero 10.0
pair_style zero 5.0 nocoeff
pair_coeff * *
pair_coeff 1 2*4 3.0 :pre
[Description:]
Define a global or per-type cutoff length for the purpose of
building a neighbor list and acquiring ghost atoms, but do
not compute any pairwise forces or energies.
This can be useful for fixes or computes which require a neighbor list
to enumerate pairs of atoms within some cutoff distance, but when
pairwise forces are not otherwise needed. Examples are the "fix
bond/create"_fix_bond_create.html, "compute rdf"_compute_rdf.html,
"compute voronoi/atom"_compute_voronoi_atom.html commands.
Note that the "comm_modify cutoff"_comm_modify.html command can be
used to insure communication of ghost atoms even when a pair style is
not defined, but it will not trigger neighbor list generation.
The optional {nocoeff} flag allows to read data files with a PairCoeff
section for any pair style. Similarly, any pair_coeff commands
will only be checked for the atom type numbers and the rest ignored.
In this case, only the global cutoff will be used.
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, or by mixing as described below:
cutoff (distance units) :ul
This coefficient is optional. If not specified, the global cutoff
specified in the pair_style command is used. If the pair_style has
been specified with the optional {nocoeff} flag, then a cutoff
pair coefficient is ignored.
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[Mixing, shift, table, tail correction, restart, rRESPA info]:
The cutoff distance for this pair style can be mixed. The default mix
value is {geometric}. See the "pair_modify" command for details.
This pair style does not support the "pair_modify"_pair_modify.html
shift, table, and tail options.
This pair style writes its information to "binary restart
files"_restart.html, 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"_run_style.html command. It does not support the
{inner}, {middle}, {outer} keywords.
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[Restrictions:] none
[Related commands:]
"pair_style none"_pair_none.html
[Default:] none