On Mon, Mar 28, 2005, Holly Freedman wrote:
> 
> I am running a simulation of acetic acid in water, and I am starting 
> with a thermalization run, where the temperature is slowly raised from 1 
> to 298K.  However the system seems to be reaching unreasonably high 
> temperatures and exploding, i.e. vlimit is exceeded.
Have you minimized the structure first?  How quickly is the temperature
rising?  It is sometimes helpful to start with a target temperature of
50 to 100 K, and later heat to 300.  But this should not be required for
the problem you describe.
So: be sure to minimize if you have not already done so.  There should be
no need for a belly flag with a small solute in water (although this doesn't
appear to be a part of the problem, but you could check.)  You might
double-check your force field generation strategy, and/or post a bit of the
output file (including the energy breakdowns).
....good luck...dac
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Received on Tue Mar 29 2005 - 18:53:00 PST