[gmx-users] Re: RE: heat appears

[Anton Feenstra]

Nguyen Hoang Phuong wrote:
> suppose that your argument is correct but the system is
> coupled to the bath i.e. my system should be as hot as the
> bath (on average). Why the Berendsen temparature coupling method
> doesn't work in this case? (temperature is increased)

It works, but not as you may expect. If something produces heat all the
time, the bath will continuously 'absorb' the excess heat, but not
instantaneous. There will be a heat flow from the system to the bath,
and the average temperature of the system will be above that of the
bath. You may think you could eliminate that by setting the coupling
time shorter (tau_t), but that will distort velocity fluctuations,
resulting in unphysical conditions.


-- 
Groetjes,

Anton
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|  _   _  ___,| K. Anton Feenstra                                     |
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