Homec4science
Diffusion lammps (lammps-icms) Browse

lammps/doc/pair_cs.html
1aeecfb0cfcflammps-icms

Last Change
Raw File

pair_cs.html
View Options

<!DOCTYPE html>
<!--[if IE 8]><html class="no-js lt-ie9" lang="en" > <![endif]-->
<!--[if gt IE 8]><!--> <html class="no-js" lang="en" > <!--<![endif]-->
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>pair_style born/coul/long/cs command &mdash; LAMMPS 15 Dec 2015 documentation</title>
<link rel="stylesheet" href="_static/css/theme.css" type="text/css" />
<link rel="stylesheet" href="_static/sphinxcontrib-images/LightBox2/lightbox2/css/lightbox.css" type="text/css" />
<link rel="top" title="LAMMPS 15 Dec 2015 documentation" href="index.html"/>
<script src="_static/js/modernizr.min.js"></script>
</head>
<body class="wy-body-for-nav" role="document">
<div class="wy-grid-for-nav">
<nav data-toggle="wy-nav-shift" class="wy-nav-side">
<div class="wy-side-nav-search">
<a href="Manual.html" class="icon icon-home"> LAMMPS
</a>
<div role="search">
<form id="rtd-search-form" class="wy-form" action="search.html" method="get">
<input type="text" name="q" placeholder="Search docs" />
<input type="hidden" name="check_keywords" value="yes" />
<input type="hidden" name="area" value="default" />
</form>
</div>
</div>
<div class="wy-menu wy-menu-vertical" data-spy="affix" role="navigation" aria-label="main navigation">
<ul>
<li class="toctree-l1"><a class="reference internal" href="Section_intro.html">1. Introduction</a></li>
<li class="toctree-l1"><a class="reference internal" href="Section_start.html">2. Getting Started</a></li>
<li class="toctree-l1"><a class="reference internal" href="Section_commands.html">3. Commands</a></li>
<li class="toctree-l1"><a class="reference internal" href="Section_packages.html">4. Packages</a></li>
<li class="toctree-l1"><a class="reference internal" href="Section_accelerate.html">5. Accelerating LAMMPS performance</a></li>
<li class="toctree-l1"><a class="reference internal" href="Section_howto.html">6. How-to discussions</a></li>
<li class="toctree-l1"><a class="reference internal" href="Section_example.html">7. Example problems</a></li>
<li class="toctree-l1"><a class="reference internal" href="Section_perf.html">8. Performance &amp; scalability</a></li>
<li class="toctree-l1"><a class="reference internal" href="Section_tools.html">9. Additional tools</a></li>
<li class="toctree-l1"><a class="reference internal" href="Section_modify.html">10. Modifying &amp; extending LAMMPS</a></li>
<li class="toctree-l1"><a class="reference internal" href="Section_python.html">11. Python interface to LAMMPS</a></li>
<li class="toctree-l1"><a class="reference internal" href="Section_errors.html">12. Errors</a></li>
<li class="toctree-l1"><a class="reference internal" href="Section_history.html">13. Future and history</a></li>
</ul>
</div>
&nbsp;
</nav>
<section data-toggle="wy-nav-shift" class="wy-nav-content-wrap">
<nav class="wy-nav-top" role="navigation" aria-label="top navigation">
<i data-toggle="wy-nav-top" class="fa fa-bars"></i>
<a href="Manual.html">LAMMPS</a>
</nav>
<div class="wy-nav-content">
<div class="rst-content">
<div role="navigation" aria-label="breadcrumbs navigation">
<ul class="wy-breadcrumbs">
<li><a href="Manual.html">Docs</a> &raquo;</li>
<li>pair_style born/coul/long/cs command</li>
<li class="wy-breadcrumbs-aside">
<a href="http://lammps.sandia.gov">Website</a>
<a href="Section_commands.html#comm">Commands</a>
</li>
</ul>
<hr/>
</div>
<div role="main" class="document" itemscope="itemscope" itemtype="http://schema.org/Article">
<div itemprop="articleBody">
<div class="section" id="pair-style-born-coul-long-cs-command">
<span id="index-0"></span><h1>pair_style born/coul/long/cs command<a class="headerlink" href="#pair-style-born-coul-long-cs-command" title="Permalink to this headline">¶</a></h1>
</div>
<div class="section" id="pair-style-buck-coul-long-cs-command">
<h1>pair_style buck/coul/long/cs command<a class="headerlink" href="#pair-style-buck-coul-long-cs-command" title="Permalink to this headline">¶</a></h1>
<div class="section" id="syntax">
<h2>Syntax<a class="headerlink" href="#syntax" title="Permalink to this headline">¶</a></h2>
<div class="highlight-python"><div class="highlight"><pre>pair_style style args
</pre></div>
</div>
<ul class="simple">
<li>style = <em>born/coul/long/cs</em> or <em>buck/coul/long/cs</em></li>
<li>args = list of arguments for a particular style</li>
</ul>
<pre class="literal-block">
<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>buck/coul/long/cs</em> args = cutoff (cutoff2)
cutoff = global cutoff for Buckingham (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<a class="headerlink" href="#examples" title="Permalink to this headline">¶</a></h2>
<div class="highlight-python"><div class="highlight"><pre>pair_style born/coul/long/cs 10.0 8.0
pair_coeff 1 1 6.08 0.317 2.340 24.18 11.51
</pre></div>
</div>
<div class="highlight-python"><div class="highlight"><pre>pair_style buck/coul/long/cs 10.0
pair_style buck/coul/long/cs 10.0 8.0
pair_coeff * * 100.0 1.5 200.0
pair_coeff 1 1 100.0 1.5 200.0 9.0
</pre></div>
</div>
</div>
<div class="section" id="description">
<h2>Description<a class="headerlink" href="#description" title="Permalink to this headline">¶</a></h2>
<p>These pair styles are designed to be used with the adiabatic
core/shell model of <a class="reference internal" href="#mitchellfinchham"><span>(Mitchell and Finchham)</span></a>. See
<a class="reference internal" href="Section_howto.html#howto-25"><span>Section_howto 25</span></a> of the manual for an
overview of the model as implemented in LAMMPS.</p>
<p>These pair styles are identical to the <a class="reference internal" href="pair_born.html"><em>pair_style born/coul/long</em></a> and <a class="reference internal" href="pair_buck.html"><em>pair_style buck/coul/long</em></a> styles, except they correctly treat the
special case where the distance between two charged core and shell
atoms in the same core/shell pair approach r = 0.0. This needs
special treatment when a long-range solver for Coulombic interactions
is also used, i.e. via the <a class="reference internal" href="kspace_style.html"><em>kspace_style</em></a> command.</p>
<p>More specifically, the short-range Coulomb interaction between a core
and its shell should be turned off using the
<a class="reference internal" href="special_bonds.html"><em>special_bonds</em></a> command by setting the 1-2 weight
to 0.0, which works because the core and shell atoms are bonded to
each other. This induces a long-range correction approximation which
fails at small distances (~&lt; 10e-8). Therefore, the Coulomb term which
is used to calculate the correction factor is extended by a minimal
distance (r_min = 1.0-6) when the interaction between a core/shell
pair is treated, as follows</p>
<img alt="_images/pair_cs.jpg" class="align-center" src="_images/pair_cs.jpg" />
<p>where C is an energy-conversion constant, Qi and Qj are the charges on
the core and shell, epsilon is the dielectric constant and r_min is the
minimal distance.</p>
</div>
<div class="section" id="restrictions">
<h2>Restrictions<a class="headerlink" href="#restrictions" title="Permalink to this headline">¶</a></h2>
<p>These pair styles are part of the CORESHELL package. They are only
enabled if LAMMPS was built with that package. See the <a class="reference internal" href="Section_start.html#start-3"><span>Making LAMMPS</span></a> section for more info.</p>
</div>
<div class="section" id="related-commands">
<h2>Related commands<a class="headerlink" href="#related-commands" title="Permalink to this headline">¶</a></h2>
<p><a class="reference internal" href="pair_coeff.html"><em>pair_coeff</em></a>, <a class="reference internal" href="pair_born.html"><em>pair_style born</em></a>,
<a class="reference internal" href="pair_buck.html"><em>pair_style buck</em></a></p>
<p><strong>Default:</strong> none</p>
<hr class="docutils" />
<p id="mitchellfinchham"><strong>(Mitchell and Finchham)</strong> Mitchell, Finchham, J Phys Condensed Matter,
5, 1031-1038 (1993).</p>
</div>
</div>
</div>
</div>
<footer>
<hr/>
<div role="contentinfo">
<p>
&copy; Copyright 2013 Sandia Corporation.
</p>
</div>
Built with <a href="http://sphinx-doc.org/">Sphinx</a> using a <a href="https://github.com/snide/sphinx_rtd_theme">theme</a> provided by <a href="https://readthedocs.org">Read the Docs</a>.
</footer>
</div>
</div>
</section>
</div>
<script type="text/javascript">
var DOCUMENTATION_OPTIONS = {
URL_ROOT:'./',
VERSION:'15 Dec 2015',
COLLAPSE_INDEX:false,
FILE_SUFFIX:'.html',
HAS_SOURCE: true
};
</script>
<script type="text/javascript" src="_static/jquery.js"></script>
<script type="text/javascript" src="_static/underscore.js"></script>
<script type="text/javascript" src="_static/doctools.js"></script>
<script type="text/javascript" src="https://cdn.mathjax.org/mathjax/latest/MathJax.js?config=TeX-AMS-MML_HTMLorMML"></script>
<script type="text/javascript" src="_static/sphinxcontrib-images/LightBox2/lightbox2/js/jquery-1.11.0.min.js"></script>
<script type="text/javascript" src="_static/sphinxcontrib-images/LightBox2/lightbox2/js/lightbox.min.js"></script>
<script type="text/javascript" src="_static/sphinxcontrib-images/LightBox2/lightbox2-customize/jquery-noconflict.js"></script>
<script type="text/javascript" src="_static/js/theme.js"></script>
<script type="text/javascript">
jQuery(function () {
SphinxRtdTheme.StickyNav.enable();
});
</script>
</body>
</html>
c4science · Help