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<div class="section" id="pair-style-zero-command">
<span id="index-0"></span><h1>pair_style zero command</h1>
<div class="section" id="syntax">
<h2>Syntax</h2>
<pre class="literal-block">
pair_style zero cutoff <em>nocoeff</em>
</pre>
<ul class="simple">
<li>zero = style name of this pair style
cutoff = global cutoff (distance units)
nocoeff = ignore all pair_coeff parameters (optional)</li>
</ul>
</div>
<div class="section" id="examples">
<h2>Examples</h2>
<div class="highlight-default"><div class="highlight"><pre><span></span><span class="n">pair_style</span> <span class="n">zero</span> <span class="mf">10.0</span>
<span class="n">pair_style</span> <span class="n">zero</span> <span class="mf">5.0</span> <span class="n">nocoeff</span>
<span class="n">pair_coeff</span> <span class="o">*</span> <span class="o">*</span>
<span class="n">pair_coeff</span> <span class="mi">1</span> <span class="mi">2</span><span class="o">*</span><span class="mi">4</span> <span class="mf">3.0</span>
</pre></div>
</div>
</div>
<div class="section" id="description">
<h2>Description</h2>
<p>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.</p>
<p>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 <a class="reference internal" href="fix_bond_create.html"><span class="doc">fix bond/create</span></a>, <a class="reference internal" href="compute_rdf.html"><span class="doc">compute rdf</span></a>,
<a class="reference internal" href="compute_voronoi_atom.html"><span class="doc">compute voronoi/atom</span></a> commands.</p>
<p>Note that the <a class="reference internal" href="comm_modify.html"><span class="doc">comm_modify cutoff</span></a> 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.</p>
<p>The optional <em>nocoeff</em> 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.</p>
<p>The following coefficients must be defined for each pair of atoms
types via the <a class="reference internal" href="pair_coeff.html"><span class="doc">pair_coeff</span></a> command as in the examples
above, or in the data file or restart files read by the
<a class="reference internal" href="read_data.html"><span class="doc">read_data</span></a> or <a class="reference internal" href="read_restart.html"><span class="doc">read_restart</span></a>
commands, or by mixing as described below:</p>
<ul class="simple">
<li>cutoff (distance units)</li>
</ul>
<p>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 <em>nocoeff</em> flag, then a cutoff
pair coefficient is ignored.</p>
<hr class="docutils" />
<p><strong>Mixing, shift, table, tail correction, restart, rRESPA info</strong>:</p>
<p>The cutoff distance for this pair style can be mixed. The default mix
value is <em>geometric</em>. See the &#8220;pair_modify&#8221; command for details.</p>
<p>This pair style does not support the <a class="reference internal" href="pair_modify.html"><span class="doc">pair_modify</span></a>
shift, table, and tail options.</p>
<p>This pair style writes its information to <a class="reference internal" href="restart.html"><span class="doc">binary restart files</span></a>, so pair_style and pair_coeff commands do not need
to be specified in an input script that reads a restart file.</p>
<p>This pair style can only be used via the <em>pair</em> keyword of the
<a class="reference internal" href="run_style.html"><span class="doc">run_style respa</span></a> command. It does not support the
<em>inner</em>, <em>middle</em>, <em>outer</em> keywords.</p>
</div>
<hr class="docutils" />
<div class="section" id="restrictions">
<h2>Restrictions</h2>
<blockquote>
<div>none</div></blockquote>
</div>
<div class="section" id="related-commands">
<h2>Related commands</h2>
<p><a class="reference internal" href="pair_none.html"><span class="doc">pair_style none</span></a></p>
<p><strong>Default:</strong> none</p>
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