[gmx-users] Specifying no temperature coupling in contrast to grompp output

Justin Lemkul jalemkul at vt.edu
Fri Dec 7 22:11:02 CET 2012

On 12/7/12 4:06 PM, Andrew DeYoung wrote:
> Hi,
> In my .mdp file, I set "tcoupl = no" and "pcoupl = no".  This way, I am
> using the NVE ensemble.  However, when I run grompp using this .mdp file,
> the grompp output includes the following line:
> Number of degrees of freedom in T-Coupling group rest is 261.00
> My question is, why does the grompp output refer to "T-Coupling" if I have
> set "tcoupl = no"?  Does this make sense?  (I have also _not_ specified
> tc_grps, tau_t, or ref_t in my .mdp file.)

More importantly, the group name specified is what is significant.  The "rest" 
group is a generic group that corresponds to everything else that is not 
actually involved.  You will see this in terms of other settings as well, like 
freeze groups or acceleration groups.



Justin A. Lemkul, Ph.D.
Research Scientist
Department of Biochemistry
Virginia Tech
Blacksburg, VA
jalemkul[at]vt.edu | (540) 231-9080


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