Homec4science
Diffusion lammps (lammm-master-deprecated) Browse

lammps/doc/fix_nve_sphere.html
c8f9dde96262lammm-master-deprecated

Last Change
Raw File

fix_nve_sphere.html
View Options

<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>
<H3>fix nve/sphere command
</H3>
<H3>fix nve/sphere/omp command
</H3>
<P><B>Syntax:</B>
</P>
<PRE>fix ID group-ID nve/sphere
</PRE>
<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>
</UL>
<P><B>Examples:</B>
</P>
<PRE>fix 1 all nve/sphere
fix 1 all nve/sphere update dipole
</PRE>
<P><B>Description:</B>
</P>
<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.
</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 use of the
<A HREF = "atom_style.html">atom_style dipole</A> command.
</P>
<HR>
<P>Styles with a <I>cuda</I>, <I>gpu</I>, <I>omp</I>, or <I>opt</I> suffix are functionally
the same as the corresponding style without the suffix. They have
been optimized to run faster, depending on your available hardware, as
discussed in <A HREF = "Section_accelerate.html">Section_accelerate</A> of the
manual. The accelerated styles take the same arguments and should
produce the same results, except for round-off and precision issues.
</P>
<P>These accelerated styles are part of the USER-CUDA, GPU, USER-OMP and OPT
packages, respectively. They are only enabled if LAMMPS was built with
those packages. See the <A HREF = "Section_start.html#start_3">Making LAMMPS</A>
section for more info.
</P>
<P>You can specify the accelerated styles explicitly in your input script
by including their suffix, or you can use the <A HREF = "Section_start.html#start_6">-suffix command-line
switch</A> when you invoke LAMMPS, or you can
use the <A HREF = "suffix.html">suffix</A> command in your input script.
</P>
<P>See <A HREF = "Section_accelerate.html">Section_accelerate</A> of the manual for
more instructions on how to use the accelerated styles effectively.
</P>
<HR>
<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>This fix requires that atoms store torque and angular velocity (omega)
and a radius as defined by the <A HREF = "atom_style.html">atom_style sphere</A>
command. If the <I>dipole</I> keyword is used, then they must also store a
dipole moment as defined by the <A HREF = "atom_style.html">atom_style dipole</A>
command.
</P>
<P>All particles in the group must be finite-size spheres. They cannot
be point particles.
</P>
<P><B>Related commands:</B>
</P>
<P><A HREF = "fix_nve.html">fix nve</A>, <A HREF = "fix_nve_asphere.html">fix nve/asphere</A>
</P>
<P><B>Default:</B> none
</P>
</HTML>
c4science · Help