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fix volume/rescale command

Syntax:

fix ID group-ID volume/rescale N keyword args ... 
  • volume/rescale = style name of this fix command
  • N = perform volume rescaling every this many timesteps
  • one or more keyword/value pairs may be appended to the args
  • keyword = x or y or z
      x, y, z args = lo,hi = desired simulation box boundaries
        at end of run 
    

    Examples:

    fix 1 all volume/rescale 100 x -9.0 9.0 z -5.0 5.0 
    

    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 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 command.

    The initial simulation box boundaries at the beginning of a run are specified by the create_box or read_data or read_restart 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. Every Nth timestep during the run, the simulation box is expanded or contracted to an ramped value between the initial and final values. 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