[gmx-users] A question on Berendsen NVT ensemble

[David van der Spoel]

On Tue, 30 Apr 2002, Lianqing Zheng wrote:

>Dear all:
>
>This is a problem on Berendsen NVT ensemble which appeared in my MD code.
>I found the equilibrium temperature is dependent on parameter Tao_T: the
>larger Tao_T, the higher the final temperature the system reaches. For
>example, the T I expect the system to reach is 7000K, however it reaches
>10000K when Tao_T is 0.1ps, 7200K when Tao_T=0.01ps, 7100K when
>Tao_T=0.005ps. The time step is 0.001ps.
>
>Do you have any insight on what's going wrong with my code?
You must have very repulsive forces. Have you checked the pressure? Most
likely you are simulating at too high a density (for the model)


Groeten, David.
________________________________________________________________________
Dr. David van der Spoel, 	Biomedical center, Dept. of Biochemistry
Husargatan 3, Box 576,  	75123 Uppsala, Sweden
phone:	46 18 471 4205		fax: 46 18 511 755
spoel at xray.bmc.uu.se	spoel at gromacs.org   http://zorn.bmc.uu.se/~spoel
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++