[gmx-users] about temperature coupling

[Mark Abraham]

On 21/11/2011 2:12 PM, RuiTing Zhang wrote:
> Dear gmxusers.
>
> I have problems about temperature coupling. Here is my parameter for temperature coupling.
>
> ; Berendsen temperature coupling is on in two groups
> Tcoupl              =  berendsen
> tc-grps		    =  System
> tau_t               =  0.1
> ref_t               =  298
>
> I used "g_traj -f traj.xtc -s topol.tpr -ot temp.xvg" to check the temperature for all time frames. The temperature of the system seems to fluctuate around 200K. My system consists 1000 waters and 18 NA and 18 CL. And the SOL alone has such problem. Could anyone give me a clue of what may be the cause of the misfit of the temperature? Thank you very much!

See g_traj -h. Your waters probably have constrained bonds.

Use g_energy to observe the observations mdrun made about the 
temperature, if you chose a suitable value for nstenergy.

Mark