On Mon, Jun 25, 2012, Sajeewa Pemasinghe wrote:
>
> I have a bellymask specified by
>
> bellymask = '(:534 < 20)& :996'
>
> I want the atoms in the above mask to be subjected to a force constant of
> 50 kcalmol-1A-2.
I think you are mistaking what a "bellymask" is; (and probably, you don't want
such a beast anyway.)
Atoms that are *not* in the belly never move (at all). It doesn't matter what
sort of force constant is involved, they just sit there.
This is both non-physical, and interacts in weird ways with barostats and
thermostats. Consider just using restraints (ntr=1) instead, but note that a
force constant of 50 kcal/mol-A2 is quite high.
The only way to have a distance-based atom selection is through the mask
terms; I don't think it is available via a group selection.
....dac
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Received on Mon Jun 25 2012 - 18:30:02 PDT
