PMASS

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PMASS = [Real]
Default: PMASS = 1000 

Description: PMASS assigns a fictitious mass (in amu) to the lattice degrees-of-freedom in case of Parrinello-Rahman dynamics (in case VASP was compiled with -Dtbdyn).


When running NpT simulations with a Langevin thermostat[1] (MDALGO=3), using the method of Parrinello and Rahman,[2][3] a fictitious mass (in amu) for the lattice degrees-of-freedom has to be assigned using the PMASS-tag. The friction coefficient for lattice degrees-of-freedom have to be specified (in ps-1) by means of the LANGEVIN_GAMMA_L-tag.

The friction coefficients γ for the atomic degrees-of-freedom are specified using the LANGEVIN_GAMMA-tag.

Related Tags and Sections

LANGEVIN_GAMMA_L, LANGEVIN_GAMMA, MDALGO

References

  1. M. P. Allen and D. J. Tildesley, Computer simulation of liquids, Oxford university press: New York, 1991.
  2. M. Parrinello and A. Rahman, Phys. Rev. Lett. 45, 1196 (1980).
  3. M. Parrinello and A. Rahman, J. Appl. Phys. 52, 7182 (1981).

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