forked from lijiext/lammps
407 lines
20 KiB
HTML
407 lines
20 KiB
HTML
|
|
|
|
<!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 buck command — LAMMPS 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 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 & 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 & 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>
|
|
|
|
</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> »</li>
|
|
|
|
<li>pair_style buck 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-buck-command">
|
|
<span id="index-0"></span><h1>pair_style buck command</h1>
|
|
</div>
|
|
<div class="section" id="pair-style-buck-cuda-command">
|
|
<h1>pair_style buck/cuda command</h1>
|
|
</div>
|
|
<div class="section" id="pair-style-buck-gpu-command">
|
|
<h1>pair_style buck/gpu command</h1>
|
|
</div>
|
|
<div class="section" id="pair-style-buck-intel-command">
|
|
<h1>pair_style buck/intel command</h1>
|
|
</div>
|
|
<div class="section" id="pair-style-buck-kk-command">
|
|
<h1>pair_style buck/kk command</h1>
|
|
</div>
|
|
<div class="section" id="pair-style-buck-omp-command">
|
|
<h1>pair_style buck/omp command</h1>
|
|
</div>
|
|
<div class="section" id="pair-style-buck-coul-cut-command">
|
|
<h1>pair_style buck/coul/cut command</h1>
|
|
</div>
|
|
<div class="section" id="pair-style-buck-coul-cut-cuda-command">
|
|
<h1>pair_style buck/coul/cut/cuda command</h1>
|
|
</div>
|
|
<div class="section" id="pair-style-buck-coul-cut-gpu-command">
|
|
<h1>pair_style buck/coul/cut/gpu command</h1>
|
|
</div>
|
|
<div class="section" id="pair-style-buck-coul-cut-intel-command">
|
|
<h1>pair_style buck/coul/cut/intel command</h1>
|
|
</div>
|
|
<div class="section" id="pair-style-buck-coul-cut-kk-command">
|
|
<h1>pair_style buck/coul/cut/kk command</h1>
|
|
</div>
|
|
<div class="section" id="pair-style-buck-coul-cut-omp-command">
|
|
<h1>pair_style buck/coul/cut/omp command</h1>
|
|
</div>
|
|
<div class="section" id="pair-style-buck-coul-long-command">
|
|
<h1>pair_style buck/coul/long command</h1>
|
|
</div>
|
|
<div class="section" id="pair-style-buck-coul-long-cs-command">
|
|
<h1>pair_style buck/coul/long/cs command</h1>
|
|
</div>
|
|
<div class="section" id="pair-style-buck-coul-long-cuda-command">
|
|
<h1>pair_style buck/coul/long/cuda command</h1>
|
|
</div>
|
|
<div class="section" id="pair-style-buck-coul-long-gpu-command">
|
|
<h1>pair_style buck/coul/long/gpu command</h1>
|
|
</div>
|
|
<div class="section" id="pair-style-buck-coul-long-intel-command">
|
|
<h1>pair_style buck/coul/long/intel command</h1>
|
|
</div>
|
|
<div class="section" id="pair-style-buck-coul-long-kk-command">
|
|
<h1>pair_style buck/coul/long/kk command</h1>
|
|
</div>
|
|
<div class="section" id="pair-style-buck-coul-long-omp-command">
|
|
<h1>pair_style buck/coul/long/omp command</h1>
|
|
</div>
|
|
<div class="section" id="pair-style-buck-coul-msm-command">
|
|
<h1>pair_style buck/coul/msm command</h1>
|
|
</div>
|
|
<div class="section" id="pair-style-buck-coul-msm-omp-command">
|
|
<h1>pair_style buck/coul/msm/omp command</h1>
|
|
<div class="section" id="syntax">
|
|
<h2>Syntax</h2>
|
|
<div class="highlight-default"><div class="highlight"><pre><span></span><span class="n">pair_style</span> <span class="n">style</span> <span class="n">args</span>
|
|
</pre></div>
|
|
</div>
|
|
<ul class="simple">
|
|
<li>style = <em>buck</em> or <em>buck/coul/cut</em> or <em>buck/coul/long</em> or <em>buck/coul/long/cs</em> or <em>buck/coul/msm</em></li>
|
|
<li>args = list of arguments for a particular style</li>
|
|
</ul>
|
|
<pre class="literal-block">
|
|
<em>buck</em> args = cutoff
|
|
cutoff = global cutoff for Buckingham interactions (distance units)
|
|
<em>buck/coul/cut</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)
|
|
<em>buck/coul/long</em> or <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)
|
|
<em>buck/coul/msm</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</h2>
|
|
<div class="highlight-default"><div class="highlight"><pre><span></span><span class="n">pair_style</span> <span class="n">buck</span> <span class="mf">2.5</span>
|
|
<span class="n">pair_coeff</span> <span class="o">*</span> <span class="o">*</span> <span class="mf">100.0</span> <span class="mf">1.5</span> <span class="mf">200.0</span>
|
|
<span class="n">pair_coeff</span> <span class="o">*</span> <span class="o">*</span> <span class="mf">100.0</span> <span class="mf">1.5</span> <span class="mf">200.0</span> <span class="mf">3.0</span>
|
|
</pre></div>
|
|
</div>
|
|
<div class="highlight-default"><div class="highlight"><pre><span></span><span class="n">pair_style</span> <span class="n">buck</span><span class="o">/</span><span class="n">coul</span><span class="o">/</span><span class="n">cut</span> <span class="mf">10.0</span>
|
|
<span class="n">pair_style</span> <span class="n">buck</span><span class="o">/</span><span class="n">coul</span><span class="o">/</span><span class="n">cut</span> <span class="mf">10.0</span> <span class="mf">8.0</span>
|
|
<span class="n">pair_coeff</span> <span class="o">*</span> <span class="o">*</span> <span class="mf">100.0</span> <span class="mf">1.5</span> <span class="mf">200.0</span>
|
|
<span class="n">pair_coeff</span> <span class="mi">1</span> <span class="mi">1</span> <span class="mf">100.0</span> <span class="mf">1.5</span> <span class="mf">200.0</span> <span class="mf">9.0</span>
|
|
<span class="n">pair_coeff</span> <span class="mi">1</span> <span class="mi">1</span> <span class="mf">100.0</span> <span class="mf">1.5</span> <span class="mf">200.0</span> <span class="mf">9.0</span> <span class="mf">8.0</span>
|
|
</pre></div>
|
|
</div>
|
|
<div class="highlight-default"><div class="highlight"><pre><span></span><span class="n">pair_style</span> <span class="n">buck</span><span class="o">/</span><span class="n">coul</span><span class="o">/</span><span class="n">long</span> <span class="mf">10.0</span>
|
|
<span class="n">pair_style</span> <span class="n">buck</span><span class="o">/</span><span class="n">coul</span><span class="o">/</span><span class="n">long</span><span class="o">/</span><span class="n">cs</span> <span class="mf">10.0</span>
|
|
<span class="n">pair_style</span> <span class="n">buck</span><span class="o">/</span><span class="n">coul</span><span class="o">/</span><span class="n">long</span> <span class="mf">10.0</span> <span class="mf">8.0</span>
|
|
<span class="n">pair_style</span> <span class="n">buck</span><span class="o">/</span><span class="n">coul</span><span class="o">/</span><span class="n">long</span><span class="o">/</span><span class="n">cs</span> <span class="mf">10.0</span> <span class="mf">8.0</span>
|
|
<span class="n">pair_coeff</span> <span class="o">*</span> <span class="o">*</span> <span class="mf">100.0</span> <span class="mf">1.5</span> <span class="mf">200.0</span>
|
|
<span class="n">pair_coeff</span> <span class="mi">1</span> <span class="mi">1</span> <span class="mf">100.0</span> <span class="mf">1.5</span> <span class="mf">200.0</span> <span class="mf">9.0</span>
|
|
</pre></div>
|
|
</div>
|
|
<div class="highlight-default"><div class="highlight"><pre><span></span><span class="n">pair_style</span> <span class="n">buck</span><span class="o">/</span><span class="n">coul</span><span class="o">/</span><span class="n">msm</span> <span class="mf">10.0</span>
|
|
<span class="n">pair_style</span> <span class="n">buck</span><span class="o">/</span><span class="n">coul</span><span class="o">/</span><span class="n">msm</span> <span class="mf">10.0</span> <span class="mf">8.0</span>
|
|
<span class="n">pair_coeff</span> <span class="o">*</span> <span class="o">*</span> <span class="mf">100.0</span> <span class="mf">1.5</span> <span class="mf">200.0</span>
|
|
<span class="n">pair_coeff</span> <span class="mi">1</span> <span class="mi">1</span> <span class="mf">100.0</span> <span class="mf">1.5</span> <span class="mf">200.0</span> <span class="mf">9.0</span>
|
|
</pre></div>
|
|
</div>
|
|
</div>
|
|
<div class="section" id="description">
|
|
<h2>Description</h2>
|
|
<p>The <em>buck</em> style computes a Buckingham potential (exp/6 instead of
|
|
Lennard-Jones 12/6) given by</p>
|
|
<img alt="_images/pair_buck.jpg" class="align-center" src="_images/pair_buck.jpg" />
|
|
<p>where rho is an ionic-pair dependent length parameter, and Rc is the
|
|
cutoff on both terms.</p>
|
|
<p>The styles with <em>coul/cut</em> or <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.
|
|
For <em>buck/coul/long</em> and <em>buc/coul/msm</em>, 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>
|
|
or <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/cut</em> and
|
|
<em>born/coul/long</em> and <em>born/coul/msm</em> styles, it is used for both the
|
|
A,C and Coulombic terms. If two cutoffs are specified, the first is
|
|
used as the cutoff for the A,C terms, and the second is the cutoff for
|
|
the Coulombic term.</p>
|
|
<p>Style <em>buck/coul/long/cs</em> is identical to <em>buck/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_born.html"><span class="doc">Born-Mayer-Huggins potential</span></a>.</p>
|
|
<div class="admonition note">
|
|
<p class="first admonition-title">Note</p>
|
|
<p class="last">For all these pair styles, the terms with A and C are always
|
|
cutoff. The additional Coulombic term can be cutoff or long-range (no
|
|
cutoff) depending on whether the style name includes coul/cut or
|
|
coul/long or coul/msm. If you wish the C/r^6 term to be long-range
|
|
(no cutoff), then see the <a class="reference internal" href="pair_buck_long.html"><span class="doc">pair_style buck/long/coul/long</span></a> command.</p>
|
|
</div>
|
|
<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:</p>
|
|
<ul class="simple">
|
|
<li>A (energy units)</li>
|
|
<li>rho (distance units)</li>
|
|
<li>C (energy-distance^6 units)</li>
|
|
<li>cutoff (distance units)</li>
|
|
<li>cutoff2 (distance units)</li>
|
|
</ul>
|
|
<p>The second coefficient, rho, must be greater than zero.</p>
|
|
<p>The latter 2 coefficients are optional. If not specified, the global
|
|
A,C and Coulombic cutoffs are used. If only one cutoff is specified,
|
|
it is used as the cutoff for both A,C and Coulombic interactions for
|
|
this type pair. If both coefficients are specified, they are used as
|
|
the A,C and Coulombic cutoffs for this type pair. You cannot specify
|
|
2 cutoffs for style <em>buck</em>, since it has no Coulombic terms.</p>
|
|
<p>For <em>buck/coul/long</em> only the LJ cutoff can be specified since a
|
|
Coulombic cutoff cannot 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>cuda</em>, <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 USER-CUDA, 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() and 1/r^6 portion of the pair interaction.</p>
|
|
<p>The <em>buck/coul/long</em> pair style supports the
|
|
<a class="reference internal" href="pair_modify.html"><span class="doc">pair_modify</span></a> table option to 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 for the A,C terms in the
|
|
pair interaction.</p>
|
|
<p>These styles write their 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>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>
|
|
<div class="section" id="restrictions">
|
|
<h2>Restrictions</h2>
|
|
<p>The <em>buck/coul/long</em> style is part of the KSPACE package. The
|
|
<em>buck/coul/long/cs</em> style is part of the CORESHELL package. They are
|
|
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_born.html"><span class="doc">pair_style born</span></a></p>
|
|
<p><strong>Default:</strong> none</p>
|
|
</div>
|
|
</div>
|
|
|
|
|
|
</div>
|
|
</div>
|
|
<footer>
|
|
|
|
|
|
<hr/>
|
|
|
|
<div role="contentinfo">
|
|
<p>
|
|
© 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:'',
|
|
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> |