Subject: RE: CCL:1 negative force constant & 2 negative frequencies

From: <[email-masked]>
Date: Tue, 14 Jun 94 11:18:41 EDT

A stationary point is.... a stationary point!!  

	Gradient-driven methods will not move off of such a point, as another
resondent has pointed out.  The best approach to start going "downhill" is to
use the potential energy distribution for the imaginary frequency to define a
*distortion coordinate*. Applying said distortion in the +ve & -ve senses may
lead to two different paths, "product" and "reactant".  Each will need to
optimized to find the low-energy form. 

	If the PE hypersurface is sufficiently complex, one may have to go thru
more than one iteration of this type to get to the global(?) minimum. 

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                           FREDERIC A. VAN-CATLEDGE

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