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.. index:: pair_style zero
pair_style zero command
=======================
Syntax
""""""
.. parsed-literal::
pair_style zero cutoff
* zero = style name of this pair style
cutoff = global cutoff (distance units)
Examples
""""""""
.. parsed-literal::
pair_style zero
pair_coeff * *
pair_coeff 1 2 3.0
Description
"""""""""""
Define a global 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 :doc:`fix bond/create <fix_bond_create>`, :doc:`compute rdf <compute_rdf>`,
:doc:`compute voronoi/atom <compute_voronoi_atom>` commands.
Note that the :doc:`comm_modify cutoff <comm_modify>` 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 following coefficients must be defined for each pair of atoms
types via the :doc:`pair_coeff <pair_coeff>` command as in the examples
above, or in the data file or restart files read by the
:doc:`read_data <read_data>` or :doc:`read_restart <read_restart>`
commands, or by mixing as described below:
* cutoff (distance units)
This coefficient is optional. If not specified, the global cutoff
specified in the pair_style command is used.
----------
**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 :doc:`pair_modify <pair_modify>`
shift, table, and tail options.
This pair style writes its information to :doc:`binary restart files <restart>`, 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
:doc:`run_style respa <run_style>` command. It does not support the
*inner*, *middle*, *outer* keywords.
----------
Restrictions
""""""""""""
none
Related commands
""""""""""""""""
:doc:`pair_style none <pair_none>`
**Default:** none
.. _lws: http://lammps.sandia.gov
.. _ld: Manual.html
.. _lc: Section_commands.html#comm