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lammps/doc/_sources/fix_nvt_sllod_eff.txt
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fix_nvt_sllod_eff.txt
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.. index:: fix nvt/sllod/eff
fix nvt/sllod/eff command
=========================
Syntax
""""""
.. parsed-literal::
fix ID group-ID nvt/sllod/eff keyword value ...
* ID, group-ID are documented in :doc:`fix <fix>` command
* nvt/sllod/eff = style name of this fix command
* additional thermostat related keyword/value pairs from the :doc:`fix nvt/eff <fix_nh_eff>` command can be appended
Examples
""""""""
.. parsed-literal::
fix 1 all nvt/sllod/eff temp 300.0 300.0 0.1
fix 1 all nvt/sllod/eff temp 300.0 300.0 0.1 drag 0.2
Description
"""""""""""
Perform constant NVT integration to update positions and velocities
each timestep for nuclei and electrons in the group for the :doc:`electron force field <pair_eff>` model, using a Nose/Hoover temperature
thermostat. V is volume; T is temperature. This creates a system
trajectory consistent with the canonical ensemble.
The operation of this fix is exactly like that described by the :doc:`fix nvt/sllod <fix_nvt_sllod>` command, except that the radius and
radial velocity of electrons are also updated and thermostatted.
Likewise the temperature calculated by the fix, using the compute it
creates (as discussed in the :doc:`fix nvt, npt, and nph <fix_nh>` doc
page), is performed with a :doc:`compute temp/deform/eff <compute_temp_deform_eff>` commmand that includes
the eFF contribution to the temperature from the electron radial
velocity.
Restart, fix_modify, output, run start/stop, minimize info
""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
This fix writes the state of the Nose/Hoover thermostat to :doc:`binary restart files <restart>`. See the :doc:`read_restart <read_restart>`
command for info on how to re-specify a fix in an input script that
reads a restart file, so that the operation of the fix continues in an
uninterrupted fashion.
The :doc:`fix_modify <fix_modify>` *temp* option is supported by this
fix. You can use it to assign a :doc:`compute <compute>` you have
defined to this fix which will be used in its thermostatting
procedure.
The :doc:`fix_modify <fix_modify>` *energy* option is supported by this
fix to add the energy change induced by Nose/Hoover thermostatting to
the system's potential energy as part of :doc:`thermodynamic output <thermo_style>`.
This fix computes the same global scalar and global vector of
quantities as does the :doc:`fix nvt/eff <fix_nh_eff>` command.
This fix can ramp its target temperature over multiple runs, using the
*start* and *stop* keywords of the :doc:`run <run>` command. See the
:doc:`run <run>` command for details of how to do this.
This fix is not invoked during :doc:`energy minimization <minimize>`.
Restrictions
""""""""""""
This fix is part of the USER-EFF 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 works best without Nose-Hoover chain thermostats, i.e. using
tchain = 1. Setting tchain to larger values can result in poor
equilibration.
Related commands
""""""""""""""""
:doc:`fix nve/eff <fix_nve_eff>`, :doc:`fix nvt/eff <fix_nh_eff>`, :doc:`fix langevin/eff <fix_langevin_eff>`, :doc:`fix nvt/sllod <fix_nvt_sllod>`, :doc:`fix_modify <fix_modify>`, :doc:`compute temp/deform/eff <compute_temp_deform_eff>`
Default
"""""""
Same as :doc:`fix nvt/eff <fix_nh_eff>`, except tchain = 1.
----------
.. _Tuckerman:
**(Tuckerman)** Tuckerman, Mundy, Balasubramanian, Klein, J Chem Phys,
106, 5615 (1997).
.. _lws: http://lammps.sandia.gov
.. _ld: Manual.html
.. _lc: Section_commands.html#comm
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