AMBER: igb10 vlimit exceeded

From: Wells, David H <>
Date: Thu, 31 Mar 2005 10:08:55 +0100

I'm trying to simulate a small organic solute in DMSO (83 molecules)
with igb=10. Previously there was trouble with solvent "penetrating" the
solute, apparently due to the way the non-bonded list is generated in
igb=10. That can be gotten around, but now simulations more than 20 ps
are blowing up. The RESTRAINT energy ramps rapidly, vlimits start to be
breached, and eventually temperature rises rapidly and solvent molecules
are forcibly ejected from the "cap" (even with FCAP=1000.0). Changing
igb=10 to igb=0 eliminates the problem.
Are the FCAP restraints only applied on atoms with indexes > NATCAP ?
Any further insights would be appreciated.
Many thanks, Dave

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Received on Thu Mar 31 2005 - 10:53:00 PST
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