2009-03-19 01:37:50 +08:00
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"LAMMPS WWW Site"_lws - "LAMMPS Documentation"_ld - "LAMMPS Commands"_lc :c
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:link(lws,http://lammps.sandia.gov)
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:link(ld,Manual.html)
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:link(lc,Section_commands.html#comm)
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:line
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fix evaporate command :h3
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[Syntax:]
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fix ID group-ID evaporate N M region-ID seed :pre
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ID, group-ID are documented in "fix"_fix.html command
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evaporate = style name of this fix command
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N = delete atoms every this many timesteps
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M = number of atoms to delete each time
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region-ID = ID of region within which to perform deletions
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seed = random number seed to use for choosing atoms to delete :ul
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[Examples:]
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fix 1 solvent evaporate 1000 10 surface 49892 :pre
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[Description:]
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Remove M atoms from the simulation every N steps. This can be used,
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for example, to model evaporation of solvent particles (i.e. drying)
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of a system. Every N steps, the number of atoms in the fix group and
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within the specifed region are counted. M of these are chosen at
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random and deleted. If there are less than M eligible particles, then
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all of them are deleted.
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Note that you cannot currently delete solvent molecules with this
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command, only individual atoms. If you delete only one atom in a
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molecule, an error will result.
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Note that neighbor lists are re-built on timesteps that atoms are
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removed. Thus you should not remove atoms too frequently or you will
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incur overhead due to the cost of building neighbor lists.
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[Restart, fix_modify, output, run start/stop, minimize info:]
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No information about this fix is written to "binary restart
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files"_restart.html. None of the "fix_modify"_fix_modify.html options
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are relevant to this fix.
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2010-04-03 00:51:06 +08:00
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This fix computes a global scalar, which can be accessed by various
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"output commands"_Section_howto.html#4_15. The scalar is the
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cummulative number of deleted atoms. The scalar value calculated by
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this fix is "intensive".
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2009-03-19 01:37:50 +08:00
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No parameter of this fix can be used with the {start/stop} keywords of
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the "run"_run.html command. This fix is not invoked during "energy
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minimization"_minimize.html.
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[Restrictions:] none
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[Related commands:]
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"fix deposit"_fix_deposit.html
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[Default:] none
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