lammps/doc/_sources/fix_nve_asphere.txt

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.. index:: fix nve/asphere
fix nve/asphere command
=======================
fix nve/asphere/intel command
=============================
Syntax
""""""
.. parsed-literal::
fix ID group-ID nve/asphere
* ID, group-ID are documented in :doc:`fix <fix>` command
* nve/asphere = style name of this fix command
Examples
""""""""
.. parsed-literal::
fix 1 all nve/asphere
Description
"""""""""""
Perform constant NVE integration to update position, velocity,
orientation, and angular velocity for aspherical 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 :doc:`fix nve <fix_nve>` command, which
assumes point particles and only updates their position and velocity.
Restart, fix_modify, output, run start/stop, minimize info
""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
No information about this fix is written to :doc:`binary restart files <restart>`. None of the :doc:`fix_modify <fix_modify>` options
are relevant to this fix. No global or per-atom quantities are stored
by this fix for access by various :ref:`output commands <howto_15>`. No parameter of this fix can
be used with the *start/stop* keywords of the :doc:`run <run>` command.
This fix is not invoked during :doc:`energy minimization <minimize>`.
----------
Styles with a *cuda*, *gpu*, *intel*, *kk*, *omp*, or *opt* 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 :doc:`Section_accelerate <Section_accelerate>`
of the manual. The accelerated styles take the same arguments and
should produce the same results, except for round-off and precision
issues.
These accelerated styles are part of the USER-CUDA, GPU, USER-INTEL,
KOKKOS, USER-OMP and OPT packages, respectively. They are only
enabled if LAMMPS was built with those packages. See the :ref:`Making LAMMPS <start_3>` section for more info.
You can specify the accelerated styles explicitly in your input script
by including their suffix, or you can use the :ref:`-suffix command-line switch <start_7>` when you invoke LAMMPS, or you can
use the :doc:`suffix <suffix>` command in your input script.
See :doc:`Section_accelerate <Section_accelerate>` of the manual for
more instructions on how to use the accelerated styles effectively.
----------
Restrictions
""""""""""""
This fix is part of the ASPHERE package. It is only enabled if LAMMPS
was built with that package. See the :ref:`Making LAMMPS <start_3>` section for more info.
This fix requires that atoms store torque and angular momementum and a
quaternion as defined by the :doc:`atom_style ellipsoid <atom_style>`
command.
All particles in the group must be finite-size. They cannot be point
particles, but they can be aspherical or spherical as defined by their
shape attribute.
Related commands
""""""""""""""""
:doc:`fix nve <fix_nve>`, :doc:`fix nve/sphere <fix_nve_sphere>`
**Default:** none
.. _lws: http://lammps.sandia.gov
.. _ld: Manual.html
.. _lc: Section_commands.html#comm