[CPMD-list] SUBTRACT COMVEL ROLVEL and Nose?

[Lan-Feng Yuan (lyuan@Princeton.EDU)]

  Hi, dear CPMD users,

  I want to make sure that the energies from CP and path integral MD only include vibrational contributions, not translational and rotational. It seems that the keyword SUBTRACT COMVEL ROLVEL would subtract global momentuam and angular momentum every given steps. The manual says that the use of these keywords is strongly recommended for long runs (e.g. >10 ps) and/or low density systems (e.g. isolated molecules, gas phase). Since I want to model water monomer and dimer, its use is "stronly recommended". However, the manual also says that since the subtracted kinetic energy is put back into the system by simple rescaling of the ionic velocities, these options is not fully compatible with NOSE thermostats ... But I surely need Nose chains in PIMD. So what to do?

  Thank you very much! Regards,

  Lan-Feng

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Dr. Lan-Feng Yuan,
Postdoctoral Associate,
Department of Chemistry,
Princeton University,
Princeton, NJ 08544, USA
Office Phone: 1-609-258-1834
Fax: 1-609-258-6746
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