Subject: 3D conformational searches

From: "Mario Citra" <[email-masked]>
Date: Thu, 02 Sep 1999 08:35:22 -0400

I was wondering what everyone's thoughts are on 3D conformational searching
algorithms such as 3DGEN or CONCORD.  I am interested in searching for the
various low energy conformers of relatively small molecules (20-50 heavy
atoms) and using these results to perform single point semi-empirical QM
calculations.  A few questions come to mind:

How close are the geometries of the low energy conformers found by the
searching algorithms to geometries obtained by semi-empirical methods ?
For example, if chemical X is found to have 10 low energy conformers by
3DGEN and I use these geometries as a starting point in an AM1 calculation
can I reasonably expect to be close to a minimum. 

What software combines 3D conformational searching algorithms with QM
calculations ?

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* Mario J. Citra  PhD		 *
* Syracuse Research Corporation	 *
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