2006-09-22 00:22:34 +08:00
2015-07-30 22:53:28 +08:00
<!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" >
2015-12-21 23:20:41 +08:00
< title > improper_coeff command — LAMMPS documentation< / title >
2015-07-30 22:53:28 +08:00
2006-09-22 00:22:34 +08:00
2015-07-30 22:53:28 +08:00
2006-09-22 00:22:34 +08:00
2015-07-30 22:53:28 +08:00
2006-09-22 00:22:34 +08:00
2015-07-30 22:53:28 +08:00
2006-09-22 00:22:34 +08:00
2015-07-30 22:53:28 +08:00
2006-09-22 00:22:34 +08:00
2015-07-30 22:53:28 +08:00
< 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" / >
2015-12-21 23:20:41 +08:00
< link rel = "top" title = "LAMMPS documentation" href = "index.html" / >
2015-07-30 22:53:28 +08:00
< 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 > improper_coeff 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 = "improper-coeff-command" >
< span id = "index-0" > < / span > < h1 > improper_coeff command< a class = "headerlink" href = "#improper-coeff-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 > improper_coeff N args
< / pre > < / div >
< / div >
< ul class = "simple" >
< li > N = improper type (see asterisk form below)< / li >
< li > args = coefficients for one or more improper types< / li >
< / ul >
< / 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 > improper_coeff 1 300.0 0.0
2006-09-22 00:22:34 +08:00
improper_coeff * 80.2 -1 2
2015-07-30 22:53:28 +08:00
improper_coeff *4 80.2 -1 2
< / pre > < / div >
< / div >
< / div >
< div class = "section" id = "description" >
< h2 > Description< a class = "headerlink" href = "#description" title = "Permalink to this headline" > ¶< / a > < / h2 >
< p > Specify the improper force field coefficients for one or more improper
2006-09-22 00:22:34 +08:00
types. The number and meaning of the coefficients depends on the
improper style. Improper coefficients can also be set in the data
2015-07-30 22:53:28 +08:00
file read by the < a class = "reference internal" href = "read_data.html" > < em > read_data< / em > < / a > command or in a restart
file.< / p >
< p > N can be specified in one of two ways. An explicit numeric value can
2006-10-03 22:37:51 +08:00
be used, as in the 1st example above. Or a wild-card asterisk can be
2006-09-22 00:22:34 +08:00
used to set the coefficients for multiple improper types. This takes
2015-07-30 22:53:28 +08:00
the form “ *” or “ < em > n” or “ n< / em > ” or “ m*n” . If N = the number of improper
2006-10-03 22:37:51 +08:00
types, then an asterisk with no numeric values means all types from 1
to N. A leading asterisk means all types from 1 to n (inclusive). A
trailing asterisk means all types from n to N (inclusive). A middle
2015-07-30 22:53:28 +08:00
asterisk means all types from m to n (inclusive).< / p >
< p > Note that using an improper_coeff command can override a previous
2006-09-22 00:22:34 +08:00
setting for the same improper type. For example, these commands set
the coeffs for all improper types, then overwrite the coeffs for just
2015-07-30 22:53:28 +08:00
improper type 2:< / p >
< div class = "highlight-python" > < div class = "highlight" > < pre > improper_coeff * 300.0 0.0
improper_coeff 2 50.0 0.0
< / pre > < / div >
< / div >
< p > A line in a data file that specifies improper coefficients uses the
2006-09-22 00:22:34 +08:00
exact same format as the arguments of the improper_coeff command in an
2006-10-03 22:37:51 +08:00
input script, except that wild-card asterisks should not be used since
2006-09-22 00:22:34 +08:00
coefficients for all N types must be listed in the file. For example,
2015-07-30 22:53:28 +08:00
under the “ Improper Coeffs” section of a data file, the line that
corresponds to the 1st example above would be listed as< / p >
< div class = "highlight-python" > < div class = "highlight" > < pre > 1 300.0 0.0
< / pre > < / div >
< / div >
< p > The < a class = "reference internal" href = "improper_class2.html" > < em > improper_style class2< / em > < / a > is an exception to
2010-11-18 02:25:09 +08:00
this rule, in that an additional argument is used in the input script
to allow specification of the cross-term coefficients. See its doc
2015-07-30 22:53:28 +08:00
page for details.< / p >
< hr class = "docutils" / >
< p > Here is an alphabetic list of improper styles defined in LAMMPS. Click on
2006-09-22 00:22:34 +08:00
the style to display the formula it computes and coefficients
2015-07-30 22:53:28 +08:00
specified by the associated < a class = "reference internal" href = "" > < em > improper_coeff< / em > < / a > command.< / p >
< p > Note that there are also additional improper styles submitted by users
2012-04-06 22:28:14 +08:00
which are included in the LAMMPS distribution. The list of these with
links to the individual styles are given in the improper section of
2015-07-30 22:53:28 +08:00
< a class = "reference internal" href = "Section_commands.html#cmd-5" > < span > this page< / span > < / a > .< / p >
< ul class = "simple" >
< li > < a class = "reference internal" href = "improper_none.html" > < em > improper_style none< / em > < / a > - turn off improper interactions< / li >
< li > < a class = "reference internal" href = "improper_hybrid.html" > < em > improper_style hybrid< / em > < / a > - define multiple styles of improper interactions< / li >
< li > < a class = "reference internal" href = "improper_class2.html" > < em > improper_style class2< / em > < / a > - COMPASS (class 2) improper< / li >
< li > < a class = "reference internal" href = "improper_cvff.html" > < em > improper_style cvff< / em > < / a > - CVFF improper< / li >
< li > < a class = "reference internal" href = "improper_harmonic.html" > < em > improper_style harmonic< / em > < / a > - harmonic improper< / li >
< li > < a class = "reference internal" href = "improper_umbrella.html" > < em > improper_style umbrella< / em > < / a > - DREIDING improper< / li >
< / ul >
< / div >
< hr class = "docutils" / >
< div class = "section" id = "restrictions" >
< h2 > Restrictions< a class = "headerlink" href = "#restrictions" title = "Permalink to this headline" > ¶< / a > < / h2 >
< p > This command must come after the simulation box is defined by a
< a class = "reference internal" href = "read_data.html" > < em > read_data< / em > < / a > , < a class = "reference internal" href = "read_restart.html" > < em > read_restart< / em > < / a > , or
< a class = "reference internal" href = "create_box.html" > < em > create_box< / em > < / a > command.< / p >
< p > An improper style must be defined before any improper coefficients are
set, either in the input script or in a data file.< / 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 = "improper_style.html" > < em > improper_style< / em > < / a > < / p >
< p > < strong > Default:< / strong > none< / p >
< / div >
< / div >
< / div >
< / div >
< footer >
< hr / >
< div role = "contentinfo" >
< p >
2015-12-11 01:23:56 +08:00
© Copyright 2013 Sandia Corporation.
2015-07-30 22:53:28 +08:00
< / 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:'./',
2015-12-21 23:20:41 +08:00
VERSION:'',
2015-07-30 22:53:28 +08:00
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 >
