[gmx-users] box exploding

[Yuguang Mu]

Dear all,
I found an interesting thing, let say, I have a molecule in a box
with the  same water model, with pme, and same equilirium process,
fixing box at first, and then let the pressure coupling on.

The different force fields turns out quite different.
one force field gives quite good density, box length converges quickly.
But one force field can not give the correct density, the box length
always grows, and in the end box exploding.

Here the general question, what main factors effect the equiliration
features of the box, I think the virial , isn't it ?

Suppose both force fields  should describe the simulated system
reasonably ? Why the pressure coupling give so different results ?

By the way, this finding is not  only a case study, I have tried
several different systems, it turns out the same.


Dr. Yuguang Mu
Institute for Physical and Theoretical Chemistry
J.W. Goethe University Frankfurt am Main
Marie Curie Str. 11
60439 Frankfurt/Main, Germany
Tel: +49-(0)69-798-29711