The ShiftMove performs a Monte Carlo move that rigidly translates the current fields by a random displacement. It is designed to be used to speed up sampling in Einstein crystal thermodynamic integration simulations under conditions in which the fraction of the Einstein crystal Hamiltonian used to define the overall Hamiltonian is very small.

See also: Rp::ShiftMove (class API)

Step Algorithm

The shift move translates the field by displacement that corresponds to a shift by an integer number of grid points in each direction. The parameter maxShift is an integer that gives the maximum allowed displacement in each direction. Displacements in each direction are chosen uniformly from the range between -maxShift and +maxShift.

Parameter file

An example of the associated parameter file block is shown below.

ShiftMove{
  probability   0.5
  maxShift        2
}

The format for this block is thus:

ShiftMove{
  probability  float (in range [0,1])
  maxShift      int 
}

The meanings of the two required parameter are summarized briefly below:

Label	Description
probability	probability of attempting a move of this type
maxShift	maximum absolute value of the shift in any direction.