lammps/doc/fix_nve_sphere.txt

"LAMMPS WWW Site"_lws - "LAMMPS Documentation"_ld - "LAMMPS Commands"_lc :c

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:link(ld,Manual.html)
:link(lc,Section_commands.html#comm)

:line

fix nve/sphere command :h3

[Syntax:]

fix ID group-ID nve/sphere :pre

ID, group-ID are documented in "fix"_fix.html command :ulb,l
nve/sphere = style name of this fix command :l
zero or more keyword/value pairs may be appended :l
keyword = {update} :l
  {update} value = {dipole}
    dipole = update orientation of dipole moment during integration :pre
:ule

[Examples:]

fix 1 all nve/sphere
fix 1 all nve/sphere update dipole :pre

[Description:]

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.

This fix differs from the "fix nve"_fix_nve.html command, which
assumes point particles and only updates their position and velocity.

If the {update} keyword is used with the {dipole} 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
"dipole"_dipole.html command.

[Restart, fix_modify, output, run start/stop, minimize info:]

No information about this fix is written to "binary restart
files"_restart.html.  None of the "fix_modify"_fix_modify.html options
are relevant to this fix.  No global or per-atom quantities are stored
by this fix for access by various "output
commands"_Section_howto.html#4_15.  No parameter of this fix can be
used with the {start/stop} keywords of the "run"_run.html command.
This fix is not invoked during "energy minimization"_minimize.html.

[Restrictions:] 

This fix requires that atoms store torque and angular velocity (omega)
as defined by the "atom_style"_atom_style.html.  It also require they
store either a per-particle diameter or per-type "shape"_shape.html.  If
the {dipole} keyword is used, then they must store a dipole moment.

All particles in the group must be finite-size spheres.  They cannot
be point particles, nor can they be aspherical.

[Related commands:]

"fix nve"_fix_nve.html, "fix nve/asphere"_fix_nve_asphere.html

[Default:] none