Re: AMBER: sander: vlimit problem

From: David A. Case <>
Date: Tue, 14 Oct 2003 15:15:02 -0700

On Mon, Oct 13, 2003, Vikas Varshney wrote:

> I tried to run constant volume simulation in sander on my system which
> contains a oligomer of PMMA, CCl4 (solvent) and an AL203 suface on one end
> of my simulation box. I kept my surface fixed usind ibelly option. When I
> saw the out put, I see all the lines something like this.
> vlimit exceeded for step 1 ; vmax = 76.24084257546498

You probably have some bad initial energies. Make sure the system is
reasonably well minimized to begin with. Try a short MD simulation, setting
ntpr=1 and look at the energies carefully. You electrostatic energy looks
very large, but I can't tell much without more information.

...good luck...dac

David A. Case                     |  e-mail:
Dept. of Molecular Biology, TPC15 |  fax:          +1-858-784-8896
The Scripps Research Institute    |  phone:        +1-858-784-9768
10550 N. Torrey Pines Rd.         |  home page:                   
La Jolla CA 92037  USA            |
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Received on Tue Oct 14 2003 - 23:53:01 PDT
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