Re: AMBER: Minimum energy tolerance gradient setting for minimization

From: David A. Case <>
Date: Tue, 6 Nov 2007 08:03:18 -0800

On Tue, Nov 06, 2007, Sandhya Tiwari wrote:
> I would like to know the method in which a minimum energy tolerance gradient
> can be adjusted for minimization in Amber 8? For example, I would like the
> number of steps to be determined by the decrease in energy (between steps)
> to be lesser or equal to 0.1 kcal/mol.

You would have to modify runmin.f to do this. Amber minimizations stop after
a given number of cycles (maxcyc) or when the rms of the elements of the
gradient vector is less than drms.

[Note that your example is rather dangerous: a given step might have an
energy decrease of less than 0.1 kcal/mol, or even an energy increase, and
yet be nowhere near converged.]


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Received on Wed Nov 07 2007 - 06:07:45 PST
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