[gmx-users] On isotropic pressure coupling

[xzp02 at mails.tsinghua.edu.cn]

Dear all:
    During simulate a polymer PBC system, I use Berendsen pressure coupling method
to get a configuration, while in the result file I found the Pressure is quite
good as I want. But Pxx, Pyy, Pzz are quite different.
--------------------------------------------------------------
Box_a     Box_b     Box_c
5.97400   5.18700   4.92600
Pressure    Pxx          Pyy         Pzz
-17.807373  1600.537476  505.298706  -2159.258301
--------------------------------------------------------------
     Is it physically resonable? Or I should use the anistropic pressure coupling
to get a pressure tensor as:
[ P/3  0   0 ]
[  0  P/3  0 ]
[  0   0  P/3]
?

   Thanks.


Best,
ZP
---------------------------------------------
Xu ZhiPing
Ph.D Candidate
Office: 3-405
Tel    : +86-10-627-83814
Department of Enginnering Mechanics
Tsinghua University
Beijing, CHINA, 100084
---------------------------------------------