[gmx-developers] More about the Ekin issue.

[hessb at mpip-mainz.mpg.de]

I think the whole NPT REMD issue (which is no longer
related to the subject) is caused by the, probably,
incorrect CVS implementation of David.

I think the highly fluctuating, meaningless instantaneous
pressure in the criterion should be replaced by the reference
pressure, as one considers an constant NPT ensemble.
Just like a constant T is used in the criterion.
The pV term then only depends on the instananeous volume,
which fluctations do have meaning.

BTW I think there is also a factor 1/PRESFAC missing in the exchange criterion.

Then there is still the barostat issue.
400 waters at 300K, p=1 bar for 10 ns give:
Berendsen volume: 11.968 rmsd 0.089
Parrinello-Rahman: 11.977 rmsd 0.150

Berk.


-------------------------------------------------
This mail sent through IMP: http://horde.org/imp/