On Sat, Feb 13, 2010, M. L. Dodson wrote:
>
> In the simulations
> showing the H-dissoc, qmshake=0 AND qmcut > cut (in the &cntrl section,
> where ntc=ntf=2, also).
Thanks for the detailed debugging. I will note that when ntf=2, there is no
bond potential. Hence, if shake gets confused, there is nothing to prevent
the protons from flying off, as you observe.
I'm not sure that there are places where one needs qmcut to be greater than
cut, since the long-range qm-mm electrostatic interactions should be handled
by PME. But I need to think about this, and we need to try to track down the
real reason why the mm bonds in question are not be shaken.
As a quick test, you might take a case that failed, and set ntf=1 to see if
that avoids dissociation.
...thanks...dave
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Received on Sat Feb 13 2010 - 19:30:03 PST
