AMBER Archive (2003)

Subject: Re: can you give me more advice about: vlimit exceeded when sander calculate free energies using TI

From: David A. Case (case_at_scripps.edu)
Date: Mon Jun 16 2003 - 10:12:05 CDT

On Mon, Jun 16, 2003, sxzheng wrote:

> I have test the system: first, just take the ligand in waterbox it can run
> normally even with TI method second, do the complex's dynamics in capwater
> condition with ibelly=0, it can run normally also with TI method third, do
> the complex's dynamics in capwater condition with ibelly=1, it can run
> normally with no Ti method, but vlimit exceeded with TI method from the
> first step in clambda=0.0.

It looks like the routines in set.f are making modifications for the regular
Hamiltonian, but not for the perturbed Hamiltonian, and this is leading to
memory corruption.

The simple advice is: don't use ibelly in this way; (use ntr=1 instead). You
could try to debug it by not calling the "set" routines and seeing if that
helps.

I am still leaning toward removing the ibelly option altogether in future
releases, at least until it can be implemented without so many side effects.

..thanks for your report....dac 

-- 

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David A. Case                     |  e-mail:      case_at_scripps.edu
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