lammps/doc/fix_reaxc_bonds.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>fix reax/c/bonds command
</H3>
<P><B>Syntax:</B>
</P>
<PRE>fix ID group-ID reax/c/bonds Nevery Nrepeat Nfreq filename
</PRE>
<UL><LI>ID, group-ID are documented in <A HREF = "fix.html">fix</A> command
<LI>reax/c/bonds = style name of this command
<LI>Nevery = output interval in timesteps
<LI>Nrepeat = # of times to use input values for calculating averages
<LI>Nfreq = calculate averages every this many timesteps
<LI>filename = name of output file
</UL>
<P><B>Examples:</B>
</P>
<PRE>fix 1 all reax/c/bonds 10 10 100 bonds.reaxc
</PRE>
<P><B>Description:</B>
</P>
<P>Write out the bond information computed by the ReaxFF potential
specified by <A HREF = "pair_reax_c.html">pair_style reax/c</A>. Bond order values
are averaged and the bond information is written to <I>filename</I> on
timesteps that are multiples of <I>Nfreq</I>, including timestep 0.
</P>
<HR>
<P>The <I>Nevery</I>, <I>Nrepeat</I>, and <I>Nfreq</I> arguments specify on what
timesteps the input values will be used in order to contribute to the
average. The final averaged quantities are generated on timesteps
that are a multiple of <I>Nfreq</I>. The average is over <I>Nrepeat</I>
quantities, computed in the preceding portion of the simulation every
<I>Nevery</I> timesteps. <I>Nfreq</I> must be a multiple of <I>Nevery</I> and
<I>Nevery</I> must be non-zero even if <I>Nrepeat</I> is 1. Also, the timesteps
contributing to the average value cannot overlap, i.e. Nfreq >
(Nrepeat-1)*Nevery is required.
</P>
<P>For example, if Nevery=2, Nrepeat=6, and Nfreq=100, then values on
timesteps 90,92,94,96,98,100 will be used to compute the final average
on timestep 100. Similarly for timesteps 190,192,194,196,198,200 on
timestep 200, etc.
</P>
<P>The format of the output file should be self-explanatory. When using
the same force field file with <A HREF = "pair_reax.html">pair_style reax</A> and
<A HREF = "pair_reax_c.html">pair_style reax/c</A>, the following commands generate
the same bond information:
</P>
<PRE>fix 1 all reax/bonds <I>N</I> bonds.reax
fix 1 all reax/c/bonds 1 1 <I>N</I> bonds.reaxc
</PRE>
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<P><B>Restart, fix_modify, output, run start/stop, minimize info:</B>
</P>
<P>No information about this fix is written to <A HREF = "restart.html">binary restart
files</A>. None of the <A HREF = "fix_modify.html">fix_modify</A> options
are relevant to this fix. No global or per-atom quantities are stored
by this fix for access by various <A HREF = "Section_howto.html#howto_15">output
commands</A>. No parameter of this fix can
be used with the <I>start/stop</I> keywords of the <A HREF = "run.html">run</A> command.
This fix is not invoked during <A HREF = "minimize.html">energy minimization</A>.
</P>
<P><B>Restrictions:</B>
</P>
<P>The fix reax/c/bonds requires that the <A HREF = "pair_reax_c.html">pair_style
reax/c</A> be invoked. This fix is part of the
USER-REAXC package. It is only enabled if LAMMPS was built with that
package. See the <A HREF = "Section_start.html#start_3">Making LAMMPS</A> section
for more info.
</P>
<P><B>Related commands:</B>
</P>
<P><A HREF = "pair_reax_c.html">pair_style reax/c</A>, <A HREF = "fix_reax_bonds.html">fix
reax/bonds</A>
</P>
<P><B>Default:</B> none
</P>
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