Dear vasp-users
According to the VASP manual, for an MD run the SMASS parameter defines the Nose mass (for SMASS >= 0). However, the quantity is not really defined in the manual.
Is this the same quantity that Nose refers (J. Chem. Phys. 81, 511 (1984)) to as Q having dimension (energy)*(time)^2 = (mass) (length)^2 ?
What unit does vasp use for SMASS? I guess atomic mass (am) as in the mass of the POTCAR file, but what about the length? Is it (am) * (Ã…)^2 ?
Help in clarifying this issue is appreciated.
<span class='smallblacktext'>[ Edited ]</span>
Units of SMASS
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sven
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Units of SMASS
Last edited by sven on Thu Feb 01, 2007 3:16 pm, edited 1 time in total.
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admin
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Units of SMASS
the Nose mass is installed rather 'sloppy', defined via the FREQUENCY with which the system couples to the thermostat, hence its units are NOT m_el* a_02 (as eg in the Bylander-Kleinman paper)
Last edited by admin on Mon Feb 12, 2007 2:23 pm, edited 1 time in total.