lammps/doc/dihedral_style_opls.html

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<CENTER><A HREF = "http://lammps.sandia.gov">LAMMPS WWW Site</A> - <A HREF = "Manual.html">LAMMPS Documentation</A> - <A HREF = "Section_commands.html#comm">LAMMPS Commands</A>
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<H3>dihedral_style opls command
</H3>
<P><B>Syntax:</B>
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<PRE>dihedral_style opls
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<P><B>Examples:</B>
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<PRE>dihedral_style opls
dihedral_coeff 1 90.0 90.0 90.0 70.0
</PRE>
<P><B>Description:</B>
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<P>The <I>opls</I> dihedral style uses the potential
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<CENTER><IMG SRC = "Eqs/dihedral_opls.jpg">
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<P>Note that the usual 1/2 factor is not included in the K values.
</P>
<P>This dihedral potential is used in the OPLS force field and is
described in <A HREF = "#Watkins">(Watkins)</A>.
</P>
<P>The following coefficients must be defined for each dihedral type via the
<A HREF = "dihedral_coeff.html">dihedral_coeff</A> command as in the example above, or in
the data file or restart files read by the <A HREF = "read_data.html">read_data</A>
or <A HREF = "read_restart.html">read_restart</A> commands:
</P>
<UL><LI>K1 (energy)
<LI>K2 (energy)
<LI>K3 (energy)
<LI>K4 (energy)
</UL>
<P><B>Restrictions:</B> none
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<P><B>Related commands:</B>
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<P><A HREF = "dihedral_coeff.html">dihedral_coeff</A>
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<P><B>Default:</B> none
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<A NAME = "Watkins"></A>
<P><B>(Watkins)</B> Watkins and Jorgensen, J Phys Chem A, 105, 4118-4125 (2001).
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