lammps/doc/pair_gauss.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>pair_style gauss command
</H3>
<P><B>Syntax:</B>
</P>
<PRE>pair_style gauss cutoff
</PRE>
<UL><LI>cutoff = global cutoff for Gauss interactions (distance units)
</UL>
<P><B>Examples:</B>
</P>
<PRE>pair_style gauss 12.0
pair_coeff * * 1.0 0.9
pair_coeff 1 4 1.0 0.9 10.0
</PRE>
<P><B>Description:</B>
</P>
<P>Style <I>gauss</I> computes a tethering potential of the form
</P>
<CENTER><IMG SRC = "Eqs/pair_gauss.jpg">
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<P>between an atom and its corresponding tether site which will typically
be a frozen atom in the simulation. Rc is the cutoff.
</P>
<P>The following coefficients must be defined for each pair of atom types
via the <A HREF = "pair_coeff.html">pair_coeff</A> command as in the examples 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>A (energy units)
<LI>B (1/distance^2 units)
<LI>cutoff (distance units)
</UL>
<P>The last coefficient is optional. If not specified, the global cutoff
is used.
</P>
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<P><B>Mixing, shift, table, tail correction, restart, rRESPA info</B>:
</P>
<P>This pair style does not support mixing. Thus, coefficients for all
I,J pairs must be specified explicitly.
</P>
<P>This pair style does not support the <A HREF = "pair_modify.html">pair_modify</A>
shift option. There is no effect due to the Gaussian well beyond the
cutoff; hence reasonable cutoffs need to be specified.
</P>
<P>The <A HREF = "pair_modify.html">pair_modify</A> table and tail options are not
relevant for this pair style.
</P>
<P>This pair style does not support the <A HREF = "pair_modify.html">pair_modify</A>
table option, since a tabulation capability does not exist for this
potential.
</P>
<P>This pair style writes its information to <A HREF = "restart.html">binary restart
files</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 <I>pair</I> keyword of the
<A HREF = "run_style.html">run_style respa</A> command. It does not support the
<I>inner</I>, <I>middle</I>, <I>outer</I> keywords.
</P>
<HR>
<P><B>Restrictions:</B> none
</P>
<P><B>Related commands:</B>
</P>
<P><A HREF = "pair_coeff.html">pair_coeff</A>, <A HREF = "fix_adapt.html">fix adapt</A>
</P>
<P><B>Default:</B> none
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