lammps/doc/html/_sources/fix_nvt_manifold_rattle.txt

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.. index:: fix nvt/manifold/rattle
fix nvt/manifold/rattle command
===============================
Syntax
""""""
.. parsed-literal::
fix ID group-ID nvt/manifold/rattle tol maxit manifold manifold-args keyword value ...
* ID, group-ID are documented in :doc:`fix <fix>` command
* nvt/manifold/rattle = style name of this fix command
* tol = tolerance to which Newton iteration must converge
* maxit = maximum number of iterations to perform
* manifold = name of the manifold
* manifold-args = parameters for the manifold
* one or more keyword/value pairs may be appended
.. parsed-literal::
keyword = *temp* or *tchain* or *every*
*temp* values = Tstart Tstop Tdamp
Tstart, Tstop = external temperature at start/end of run
Tdamp = temperature damping parameter (time units)
*tchain* value = N
N = length of thermostat chain (1 = single thermostat)
*every* value = N
N = print info about iteration every N steps. N = 0 means no output
Examples
""""""""
fix 1 all nvt/manifold/rattle 1e-4 10 cylinder 3.0 temp 1.0 1.0 10.0
Description
"""""""""""
This fix combines the RATTLE-based :ref:`(Andersen) <Andersen>` time integrator of :doc:`fix nve/manifold/rattle <fix_nve_manifold_rattle>` :ref:`(Paquay) <Paquay>` with a Nose-Hoover-chain thermostat to sample the
canonical ensemble of particles constrained to a curved surface (manifold). This sampling does suffer from discretization bias of O(dt).
For a list of currently supported manifolds and their parameters, see :doc:`manifolds <manifolds>`
----------
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>`.
----------
Restrictions
""""""""""""
This fix is part of the USER-MANIFOLD package. It is only enabled if LAMMPS
was built with that package. See the :ref:`Making LAMMPS <start_3>`
section for more info.
Only use this with *min_style hftn* or *min_style quickmin*\ . If not, the constraints
will not be satisfied very well at all. A warning is generated if the *min_style* is
incompatible but no error.
----------
Related commands
""""""""""""""""
:doc:`fix nve/manifold/rattle <fix_nvt_manifold_rattle>`, :doc:`fix manifoldforce <fix_manifoldforce>`
**Default:** every = 0
----------
.. _Andersen:
**(Andersen)** Andersen, J. Comp. Phys. 52, 24, (1983).
.. _Paquay:
**(Paquay)** Paquay and Kusters, Biophys. J., 110, ???, (2016), to be published,
preprint available at `arXiv:1411.3019 <http://arxiv.org/abs/1411.3019/>`_.
.. _lws: http://lammps.sandia.gov
.. _ld: Manual.html
.. _lc: Section_commands.html#comm