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Hello,

I wish to use Nos?-Hoover thermostat to simulate a canonical ensemble. I found in a paper that smass Q ~ g.kB.T/w2 ; thus I made a histogram with the vibrational frequencies of my system, and found a mean frequency w = 1336 cm-1. Now I'd like to calculate Q for a given temperature, yet I have no idea in which unit I have to write w and kB for Q to be inserted in INCAR... Should I use w in cm-1 or in Hz ? kB in eV/K or J/K ?

Also, the events I'm interested in to simulate happen in about 2.5 ps, according to publications ; yet VASP aks the time step to be in fs in the INCAR file. Do you think I'll be able to observe them in a reasonable simulation time if I choose a big time step, or is it impossible ?

Thank you very much for your help !

I suggest that, the set for timestep depends on nature of your system and quesitons you want to deal with. If no H atom inculded, the POTIM = 2 or 2.5 would be accepted.

I am not sure that VASP can run a MD with Nose-Hoover thermostat? It is Nose thermostat or Nose Hoover thermostat will be chose for SMASS >=0?

<span class='smallblacktext'>[ Edited Sun Sep 16 2012, 02:45AM ]</span>