2008-03-18 08:24:08 +08:00
|
|
|
<HTML>
|
|
|
|
|
<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>
|
|
|
|
|
</CENTER>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<HR>
|
|
|
|
|
|
2008-03-19 04:56:15 +08:00
|
|
|
<H3>fix nve/sphere command
|
2008-03-18 08:24:08 +08:00
|
|
|
</H3>
|
|
|
|
|
<P><B>Syntax:</B>
|
|
|
|
|
</P>
|
2008-03-19 04:56:15 +08:00
|
|
|
<PRE>fix ID group-ID nve/sphere
|
2008-03-18 08:24:08 +08:00
|
|
|
</PRE>
|
2008-03-19 04:56:15 +08:00
|
|
|
<UL><LI>ID, group-ID are documented in <A HREF = "fix.html">fix</A> command
|
|
|
|
|
|
|
|
|
|
<LI>nve/sphere = style name of this fix command
|
|
|
|
|
|
|
|
|
|
<LI>zero or more keyword/value pairs may be appended
|
|
|
|
|
|
|
|
|
|
<LI>keyword = <I>update</I>
|
|
|
|
|
|
|
|
|
|
<PRE> <I>update</I> value = <I>dipole</I>
|
|
|
|
|
dipole = update orientation of dipole moment during integration
|
|
|
|
|
</PRE>
|
|
|
|
|
|
2008-03-18 08:24:08 +08:00
|
|
|
</UL>
|
|
|
|
|
<P><B>Examples:</B>
|
|
|
|
|
</P>
|
2008-03-19 04:56:15 +08:00
|
|
|
<PRE>fix 1 all nve/sphere
|
|
|
|
|
fix 1 all nve/sphere update dipole
|
2008-03-18 08:24:08 +08:00
|
|
|
</PRE>
|
|
|
|
|
<P><B>Description:</B>
|
|
|
|
|
</P>
|
2008-03-20 06:51:12 +08:00
|
|
|
<P>Perform constant NVE integration to update position, velocity, and
|
|
|
|
|
angular velocity for extended spherical particles in the group each
|
|
|
|
|
timestep. V is volume; E is energy. This creates a system trajectory
|
|
|
|
|
consistent with the microcanonical ensemble.
|
2008-03-19 04:56:15 +08:00
|
|
|
</P>
|
|
|
|
|
<P>This fix differs from the <A HREF = "fix_nve.html">fix nve</A> command, which
|
|
|
|
|
assumes point particles and only updates their position and velocity.
|
|
|
|
|
</P>
|
|
|
|
|
<P>If the <I>update</I> keyword is used with the <I>dipole</I> value, then the
|
|
|
|
|
orientation of the dipole moment of each particle is also updated
|
|
|
|
|
during the time integration. This option should be used for models
|
|
|
|
|
where a dipole moment is assigned to particles via the
|
|
|
|
|
<A HREF = "dipole.html">dipole</A> command.
|
2008-03-18 08:24:08 +08:00
|
|
|
</P>
|
|
|
|
|
<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 scalar or vector or per-atom
|
|
|
|
|
quantities are stored by this fix for access by various <A HREF = "Section_howto.html#4_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>
|
2009-06-27 02:22:33 +08:00
|
|
|
<P>This fix requires that atoms store torque and angular velocity (omega)
|
|
|
|
|
as defined by the <A HREF = "atom_style.html">atom_style</A>. It also require they
|
|
|
|
|
store either a per-particle diameter or per-type <A HREF = "shape.html">shape</A>. If
|
|
|
|
|
the <I>dipole</I> keyword is used, then they must store a dipole moment.
|
|
|
|
|
</P>
|
|
|
|
|
<P>All particles in the group must be finite-size spheres. They cannot
|
|
|
|
|
be point particles, nor can they be aspherical.
|
2008-03-18 08:24:08 +08:00
|
|
|
</P>
|
|
|
|
|
<P><B>Related commands:</B>
|
|
|
|
|
</P>
|
2008-03-19 04:56:15 +08:00
|
|
|
<P><A HREF = "fix_nve.html">fix nve</A>, <A HREF = "fix_nve_asphere.html">fix nve/asphere</A>
|
2008-03-18 08:24:08 +08:00
|
|
|
</P>
|
|
|
|
|
<P><B>Default:</B> none
|
|
|
|
|
</P>
|
|
|
|
|
</HTML>
|
