lammps/doc/fix_volume_rescale.txt

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"LAMMPS WWW Site"_lws - "LAMMPS Documentation"_ld - "LAMMPS Commands"_lc :c
:link(lws,http://lammps.sandia.gov)
:link(ld,Manual.html)
:link(lc,Section_commands.html#comm)
:line
fix volume/rescale command :h3
[Syntax:]
fix ID group-ID volume/rescale N keyword args ... :pre
ID, group-ID are documented in "fix"_fix.html command :ul
volume/rescale = style name of this fix command :l
N = perform volume rescaling every this many timesteps :l
one or more keyword/value pairs may be appended to the args :l
keyword = {x} or {y} or {z} :l
{x}, {y}, {z} args = lo,hi = desired simulation box boundaries
at end of run (distance units) :pre
:ule
[Examples:]
fix 1 all volume/rescale 100 x -9.0 9.0 z -5.0 5.0 :pre
[Description:]
Enable a volume (density) change during a simulation. Each of the 3
box dimensions is controlled separately. Any dimension being varied
by this command must be periodic - see the "boundary"_boundary.html
command. Dimensions not varied by this command can be periodic or
non-periodic. The volume associated with an unspecified dimension can
also be controlled by a "fix npt"_fix_npt.html command.
The initial simulation box boundaries at the beginning of a run are
specified by the "create_box"_create_box.html or
"read_data"_read_data.html or "read_restart"_read_restart.html command
used to setup the simulation, or they are the values at the end of the
previous run. The desired simulation box boundaries at the end of the
run are given by the {lo} and {hi} arguments. See the
"units"_units.html command for a discussion of distance units.
Every Nth timestep during the run, the simulation box is expanded or
contracted to a ramped value between the initial and final values.
The "run"_run.html command documents how to make the ramping take
place across multiple runs. The coordinates of all atoms in the group
are also scaled to the new box size.
[Restrictions:]
Any dimension being varied by this fix must be periodic.
[Related commands:] none
[Default:] none