Nose-Hoover heat bath mass|
- Date: 2019/09/12 18:56
- Name: Pavel Ondracka
- Hi, I have a question regarding the "heat bath mass" for the Nose-Hoover thermostat.
I was trying to figure out how to set it properly for my system. I did some reading on the topic and ended with some useful formulas, for example for the effective relaxation time teff^2 = Q/(N*kB*T0), where Q is the "heat bath mass", N is the number of degrees of freedom, kB Boltzmann constant and T0 is the temperature.
The problematic part is that in those examples (as well as in the Nose's original article) the units of the Q are [m^2.kg] (to cite Nose: "Q is a parameter of dimension energy·(time)2 and behaves as a mass for the motion of s), while the openmx manual states that the "heat bath mass" is in atomic mass units, which implies to me that the dimension is just mass. How do I convert from the openmx "heat bath mass" parameter to the Q parameter with m^2.kg in SI units as used for example in the Nose's article?