78 lines
2.3 KiB
ReStructuredText
78 lines
2.3 KiB
ReStructuredText
.. index:: temper/npt
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temper/npt command
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==================
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Syntax
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""""""
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.. parsed-literal::
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temper/npt N M temp fix-ID seed1 seed2 pressure index
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* N = total # of timesteps to run
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* M = attempt a tempering swap every this many steps
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* temp = initial temperature for this ensemble
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* fix-ID = ID of the fix that will control temperature and pressure during the run
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* seed1 = random # seed used to decide on adjacent temperature to partner with
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* seed2 = random # seed for Boltzmann factor in Metropolis swap
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* pressure = setpoint pressure for the ensemble
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* index = which temperature (0 to N-1) I am simulating (optional)
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Examples
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""""""""
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.. code-block:: LAMMPS
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temper/npt 100000 100 $t nptfix 0 58728 1
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temper/npt 2500000 1000 300 nptfix 0 32285 $p
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temper/npt 5000000 2000 $t nptfix 0 12523 1 $w
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Description
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"""""""""""
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Run a parallel tempering or replica exchange simulation using multiple
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replicas (ensembles) of a system in the isothermal-isobaric (NPT)
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ensemble. The command temper/npt works like :doc:`temper <temper>` but
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requires running replicas in the NPT ensemble instead of the canonical
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(NVT) ensemble and allows for pressure to be set in the ensembles.
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These multiple ensembles can run in parallel at different temperatures
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or different pressures. The acceptance criteria for temper/npt is
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specific to the NPT ensemble and can be found in references
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:ref:`(Okabe) <Okabe2>` and :ref:`(Mori) <Mori2>`.
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Apart from the difference in acceptance criteria and the specification
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of pressure, this command works much like the :doc:`temper <temper>`
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command. See the documentation on :doc:`temper <temper>` for information
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on how the parallel tempering is handled in general.
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----------
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Restrictions
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""""""""""""
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This command can only be used if LAMMPS was built with the USER-MISC
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package. See the :doc:`Build package <Build_package>` doc page for more
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info.
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This command should be used with a fix that maintains the
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isothermal-isobaric (NPT) ensemble.
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Related commands
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""""""""""""""""
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:doc:`temper <temper>`, :doc:`variable <variable>`, :doc:`fix_npt <fix_nh>`
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Default
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"""""""
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none
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.. _Okabe2:
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**(Okabe)** T. Okabe, M. Kawata, Y. Okamoto, M. Masuhiro, Chem. Phys. Lett., 335, 435-439 (2001).
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.. _Mori2:
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**(Mori)** Y. Mori, Y. Okamoto, J. Phys. Soc. Jpn., 7, 074003 (2010).
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