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<div class="section" id="pair-style-born-command">
<span id="index-0"></span><h1>pair_style born command</h1>
</div>
<div class="section" id="pair-style-born-omp-command">
<h1>pair_style born/omp command</h1>
</div>
<div class="section" id="pair-style-born-gpu-command">
<h1>pair_style born/gpu command</h1>
</div>
<div class="section" id="pair-style-born-coul-long-command">
<h1>pair_style born/coul/long command</h1>
</div>
<div class="section" id="pair-style-born-coul-long-cs-command">
<h1>pair_style born/coul/long/cs command</h1>
</div>
<div class="section" id="pair-style-born-coul-long-gpu-command">
<h1>pair_style born/coul/long/gpu command</h1>
</div>
<div class="section" id="pair-style-born-coul-long-omp-command">
<h1>pair_style born/coul/long/omp command</h1>
</div>
<div class="section" id="pair-style-born-coul-msm-command">
<h1>pair_style born/coul/msm command</h1>
</div>
<div class="section" id="pair-style-born-coul-msm-omp-command">
<h1>pair_style born/coul/msm/omp command</h1>
</div>
<div class="section" id="pair-style-born-coul-wolf-command">
<h1>pair_style born/coul/wolf command</h1>
</div>
<div class="section" id="pair-style-born-coul-wolf-gpu-command">
<h1>pair_style born/coul/wolf/gpu command</h1>
</div>
<div class="section" id="pair-style-born-coul-wolf-omp-command">
<h1>pair_style born/coul/wolf/omp command</h1>
<div class="section" id="syntax">
<h2>Syntax</h2>
<pre class="literal-block">
pair_style style args
</pre>
<ul class="simple">
<li>style = <em>born</em> or <em>born/coul/long</em> or <em>born/coul/long/cs</em> or <em>born/coul/msm</em> or <em>born/coul/wolf</em></li>
<li>args = list of arguments for a particular style</li>
</ul>
<pre class="literal-block">
<em>born</em> args = cutoff
cutoff = global cutoff for non-Coulombic interactions (distance units)
<em>born/coul/long</em> or <em>born/coul/long/cs</em> args = cutoff (cutoff2)
cutoff = global cutoff for non-Coulombic (and Coulombic if only 1 arg) (distance units)
cutoff2 = global cutoff for Coulombic (optional) (distance units)
<em>born/coul/msm</em> args = cutoff (cutoff2)
cutoff = global cutoff for non-Coulombic (and Coulombic if only 1 arg) (distance units)
cutoff2 = global cutoff for Coulombic (optional) (distance units)
<em>born/coul/wolf</em> args = alpha cutoff (cutoff2)
alpha = damping parameter (inverse distance units)
cutoff = global cutoff for non-Coulombic (and Coulombic if only 1 arg) (distance units)
cutoff2 = global cutoff for Coulombic (optional) (distance units)
</pre>
</div>
<div class="section" id="examples">
<h2>Examples</h2>
<pre class="literal-block">
pair_style born 10.0
pair_coeff * * 6.08 0.317 2.340 24.18 11.51
pair_coeff 1 1 6.08 0.317 2.340 24.18 11.51
</pre>
<pre class="literal-block">
pair_style born/coul/long 10.0
pair_style born/coul/long/cs 10.0
pair_style born/coul/long 10.0 8.0
pair_style born/coul/long/cs 10.0 8.0
pair_coeff * * 6.08 0.317 2.340 24.18 11.51
pair_coeff 1 1 6.08 0.317 2.340 24.18 11.51
</pre>
<pre class="literal-block">
pair_style born/coul/msm 10.0
pair_style born/coul/msm 10.0 8.0
pair_coeff * * 6.08 0.317 2.340 24.18 11.51
pair_coeff 1 1 6.08 0.317 2.340 24.18 11.51
</pre>
<pre class="literal-block">
pair_style born/coul/wolf 0.25 10.0
pair_style born/coul/wolf 0.25 10.0 9.0
pair_coeff * * 6.08 0.317 2.340 24.18 11.51
pair_coeff 1 1 6.08 0.317 2.340 24.18 11.51
</pre>
</div>
<div class="section" id="description">
<h2>Description</h2>
<p>The <em>born</em> style computes the Born-Mayer-Huggins or Tosi/Fumi
potential described in <a class="reference internal" href="#fumitosi"><span class="std std-ref">(Fumi and Tosi)</span></a>, given by</p>
<img alt="_images/pair_born.jpg" class="align-center" src="_images/pair_born.jpg" />
<p>where sigma is an interaction-dependent length parameter, rho is an
ionic-pair dependent length parameter, and Rc is the cutoff.</p>
<p>The styles with <em>coul/long</em> or <em>coul/msm</em> add a Coulombic term as
described for the <a class="reference internal" href="pair_lj.html"><span class="doc">lj/cut</span></a> pair styles. An additional
damping factor is applied to the Coulombic term so it can be used in
conjunction with the <a class="reference internal" href="kspace_style.html"><span class="doc">kspace_style</span></a> command and its
<em>ewald</em> or <em>pppm</em> of <em>msm</em> option. The Coulombic cutoff specified for
this style means that pairwise interactions within this distance are
computed directly; interactions outside that distance are computed in
reciprocal space.</p>
<p>If one cutoff is specified for the <em>born/coul/long</em> and
<em>born/coul/msm</em> style, it is used for both the A,C,D and Coulombic
terms. If two cutoffs are specified, the first is used as the cutoff
for the A,C,D terms, and the second is the cutoff for the Coulombic
term.</p>
<p>The <em>born/coul/wolf</em> style adds a Coulombic term as described for the
Wolf potential in the <a class="reference internal" href="pair_coul.html"><span class="doc">coul/wolf</span></a> pair style.</p>
<p>Style <em>born/coul/long/cs</em> is identical to <em>born/coul/long</em> except that
a term is added for the <a class="reference internal" href="Section_howto.html#howto-25"><span class="std std-ref">core/shell model</span></a>
to allow charges on core and shell particles to be separated by r =
0.0.</p>
<p>Note that these potentials are related to the <a class="reference internal" href="pair_buck.html"><span class="doc">Buckingham potential</span></a>.</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>A (energy units)</li>
<li>rho (distance units)</li>
<li>sigma (distance units)</li>
<li>C (energy units * distance units^6)</li>
<li>D (energy units * distance units^8)</li>
<li>cutoff (distance units)</li>
</ul>
<p>The second coefficient, rho, must be greater than zero.</p>
<p>The last coefficient is optional. If not specified, the global A,C,D
cutoff specified in the pair_style command is used.</p>
<p>For <em>born/coul/long</em> and <em>born/coul/wolf</em> no Coulombic cutoff can be
specified for an individual I,J type pair. All type pairs use the
same global Coulombic cutoff specified in the pair_style command.</p>
<hr class="docutils" />
<p>Styles with a <em>gpu</em>, <em>intel</em>, <em>kk</em>, <em>omp</em>, or <em>opt</em> suffix are
functionally the same as the corresponding style without the suffix.
They have been optimized to run faster, depending on your available
hardware, as discussed in <a class="reference internal" href="Section_accelerate.html"><span class="doc">Section_accelerate</span></a>
of the manual. The accelerated styles take the same arguments and
should produce the same results, except for round-off and precision
issues.</p>
<p>These accelerated styles are part of the GPU, USER-INTEL, KOKKOS,
USER-OMP and OPT packages, respectively. They are only enabled if
LAMMPS was built with those packages. See the <a class="reference internal" href="Section_start.html#start-3"><span class="std std-ref">Making LAMMPS</span></a> section for more info.</p>
<p>You can specify the accelerated styles explicitly in your input script
by including their suffix, or you can use the <a class="reference internal" href="Section_start.html#start-7"><span class="std std-ref">-suffix command-line switch</span></a> when you invoke LAMMPS, or you can
use the <a class="reference internal" href="suffix.html"><span class="doc">suffix</span></a> command in your input script.</p>
<p>See <a class="reference internal" href="Section_accelerate.html"><span class="doc">Section_accelerate</span></a> of the manual for
more instructions on how to use the accelerated styles effectively.</p>
<hr class="docutils" />
<p><strong>Mixing, shift, table, tail correction, restart, rRESPA info</strong>:</p>
<p>These pair styles do not support mixing. Thus, coefficients for all
I,J pairs must be specified explicitly.</p>
<p>These styles support the <a class="reference internal" href="pair_modify.html"><span class="doc">pair_modify</span></a> shift option
for the energy of the exp(), 1/r^6, and 1/r^8 portion of the pair
interaction.</p>
<p>The <em>born/coul/long</em> pair style supports the
<a class="reference internal" href="pair_modify.html"><span class="doc">pair_modify</span></a> table option ti tabulate the
short-range portion of the long-range Coulombic interaction.</p>
<p>These styles support the pair_modify tail option for adding long-range
tail corrections to energy and pressure.</p>
<p>Thess styles writes thei information to binary <a class="reference internal" href="restart.html"><span class="doc">restart</span></a>
files, so pair_style and pair_coeff commands do not need to be
specified in an input script that reads a restart file.</p>
<p>These styles 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. They do 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>
<p>The <em>born/coul/long</em> style is part of the KSPACE package. It is only
enabled if LAMMPS was built with that package (which it is by
default). See the <a class="reference internal" href="Section_start.html#start-3"><span class="std std-ref">Making LAMMPS</span></a> section
for more info.</p>
</div>
<div class="section" id="related-commands">
<h2>Related commands</h2>
<p><a class="reference internal" href="pair_coeff.html"><span class="doc">pair_coeff</span></a>, <a class="reference internal" href="pair_buck.html"><span class="doc">pair_style buck</span></a></p>
<p><strong>Default:</strong> none</p>
<hr class="docutils" />
<p id="fumitosi">Fumi and Tosi, J Phys Chem Solids, 25, 31 (1964),
Fumi and Tosi, J Phys Chem Solids, 25, 45 (1964).</p>
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