Homec4science
Diffusion lammps (lammps-icms) Browse

lammps/doc/pair_awpmd.html
9a1aa45a4423lammps-icms

Last Change
Raw File

pair_awpmd.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 awpmd/cut command &mdash; LAMMPS 15 May 2015 version 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 May 2015 version 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 awpmd/cut command</li>
<li class="wy-breadcrumbs-aside">
<a href="http://lammps.sandia.gov">Homepage</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-awpmd-cut-command">
<span id="index-0"></span><h1>pair_style awpmd/cut command<a class="headerlink" href="#pair-style-awpmd-cut-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 awpmd/cut Rc keyword value ...
</pre></div>
</div>
<ul class="simple">
<li>Rc = global cutoff, -1 means cutoff of half the shortest box length</li>
<li>zero or more keyword/value pairs may be appended</li>
<li>keyword = <em>hartree</em> or <em>dproduct</em> or <em>uhf</em> or <em>free</em> or <em>pbc</em> or <em>fix</em> or <em>harm</em> or <em>ermscale</em> or <em>flex_press</em></li>
</ul>
<pre class="literal-block">
<em>hartree</em> value = none
<em>dproduct</em> value = none
<em>uhf</em> value = none
<em>free</em> value = none
<em>pbc</em> value = Plen
Plen = periodic width of electron = -1 or positive value (distance units)
<em>fix</em> value = Flen
Flen = fixed width of electron = -1 or positive value (distance units)
<em>harm</em> value = width
width = harmonic width constraint
<em>ermscale</em> value = factor
factor = scaling between electron mass and width variable mass
<em>flex_press</em> value = none
</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 awpmd/cut -1
pair_style awpmd/cut 40.0 uhf free
pair_coeff * *
pair_coeff 2 2 20.0
</pre></div>
</div>
</div>
<div class="section" id="description">
<h2>Description<a class="headerlink" href="#description" title="Permalink to this headline">¶</a></h2>
<p>This pair style contains an implementation of the Antisymmetrized Wave
Packet Molecular Dynamics (AWPMD) method. Need citation here. Need
basic formulas here. Could be links to other documents.</p>
<p>Rc is the cutoff.</p>
<p>The pair_style command allows for several optional keywords
to be specified.</p>
<p>The <em>hartree</em>, <em>dproduct</em>, and <em>uhf</em> keywords specify the form of the
initial trial wave function for the system. If the <em>hartree</em> keyword
is used, then a Hartree multielectron trial wave function is used. If
the <em>dproduct</em> keyword is used, then a trial function which is a
product of two determinants for each spin type is used. If the <em>uhf</em>
keyword is used, then an unrestricted Hartree-Fock trial wave function
is used.</p>
<p>The <em>free</em>, <em>pbc</em>, and <em>fix</em> keywords specify a width constraint on
the electron wavepackets. If the <em>free</em> keyword is specified, then there is no
constraint. If the <em>pbc</em> keyword is used and <em>Plen</em> is specified as
-1, then the maximum width is half the shortest box length. If <em>Plen</em>
is a positive value, then the value is the maximum width. If the
<em>fix</em> keyword is used and <em>Flen</em> is specified as -1, then electrons
have a constant width that is read from the data file. If <em>Flen</em> is a
positive value, then the constant width for all electrons is set to
<em>Flen</em>.</p>
<p>The <em>harm</em> keyword allow oscillations in the width of the
electron wavepackets. More details are needed.</p>
<p>The <em>ermscale</em> keyword specifies a unitless scaling factor
between the electron masses and the width variable mass. More
details needed.</p>
<p>If the <em>flex_press</em> keyword is used, then a contribution from the
electrons is added to the total virial and pressure of the system.</p>
<p>This potential is designed to be used with <a class="reference internal" href="atom_style.html"><em>atom_style wavepacket</em></a> definitions, in order to handle the
description of systems with interacting nuclei and explicit electrons.</p>
<p>The following coefficients must be defined for each pair of atoms
types via the <a class="reference internal" href="pair_coeff.html"><em>pair_coeff</em></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"><em>read_data</em></a> or <a class="reference internal" href="read_restart.html"><em>read_restart</em></a>
commands, or by mixing as described below:</p>
<ul class="simple">
<li>cutoff (distance units)</li>
</ul>
<p>For <em>awpmd/cut</em>, the cutoff coefficient is optional. If it is not
used (as in some of the examples above), the default global value
specified in the pair_style command is used.</p>
<hr class="docutils" />
<p><strong>Mixing, shift, table, tail correction, restart, rRESPA info</strong>:</p>
<p>The <a class="reference internal" href="pair_modify.html"><em>pair_modify</em></a> mix, shift, table, and tail options
are not relevant for this pair style.</p>
<p>This pair style writes its information to <a class="reference internal" href="restart.html"><em>binary restart files</em></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"><em>run_style respa</em></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<a class="headerlink" href="#restrictions" title="Permalink to this headline">¶</a></h2>
<blockquote>
<div>none</div></blockquote>
</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></p>
</div>
<div class="section" id="default">
<h2>Default<a class="headerlink" href="#default" title="Permalink to this headline">¶</a></h2>
<p>These are the defaults for the pair_style keywords: <em>hartree</em> for the
initial wavefunction, <em>free</em> for the wavepacket width.</p>
</div>
</div>
</div>
</div>
<footer>
<hr/>
<div role="contentinfo">
<p>
&copy; Copyright .
</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 May 2015 version',
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="_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