Subject: complex geom calc protocol

From: Goutam Das <[email-masked]>
Date: Wed, 13 Jan 1999 20:38:36 -0600

Here are two more responses to my originial questions which goes as follows:
A very big thank you to everyone who responded.

"I wonder whether there are protocols (besides MD sim) for calculating
geometries (ab initio/semiempiric/molmech) of  minima's and finally glob
minimas  for pairs of simple molecules. If there are, I would deeply
appreciate if anyone could kindly point me to good references.  Normally I
optimize geom's of both mol's, then freeze the crd's of each and then move
one relative to another and then relax all constraints, guessing inital
geoms by intuition--I am sure I  miss a lot of conf's and maybe certainly
the glob min (although I understand that there is no guarantee that any
particular method could give the global min).  However, there should be a
much better & efficient subroutine."

Date: Tue, 05 Jan 1999 09:13:07 -0600
From: "Mark A. Zottola" <[email-masked]>
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To: Goutam Das <[email-masked]>
Subject: Global Minima

Dear Dr. Das,

I do not have the reference on hand, but I do know that in the late 80's
Dr. Scheraga published a paper on an algorithm for finding the global
minimum for a geometry by manipulating the dimensionality of the
problem. I believe instead of working in n-space and doing a geometry
minimization (which is almost guaranteed to NOT find the global
minimum), Scheraga's approach (I believe, check the paper) works on
starting with a low dimensionality then adding complexity, the idea
being that if you approach the problem from the downside, the first
point you should hit would be the global minimum...

Good luck finding the reference. If I manage to run across it I will
send it to you.

Best of luck in your research!
--
*********
Mark A. Zottola                       Alabama Research and Education
Network
119 Rust Research Center              Nichols Research Corporation
University of Alabama-Birmingham      VOICE:  (205) 934-3893
Birmingham, AL  35294                 EMAIL:  [email-masked]

From: [email-masked]
Date: Mon, 4 Jan 1999 20:57:55 -0800 (PST)
To: [email-masked]
Subject: Re:  CCL:complex geom calcn protocol

You might find 'molecular silverware' by people at Rohm-Haas (Hass?)
of interest. It was written up in J. Comp. Chem. a few years ago.

Bill Ross

GOUTAM  DAS, Ph.D
BETZDEARBORN (A division of Hercules)
PO BOX 4300, 9669 GROGANS MILL ROAD
THE WOODLANDS, TX 77387-4300
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