From cmao771[ AT ]charon.chpc.utexas.edu  Tue Jan 11 15:49:16 1994
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From: cmao771 "at@at" charon.chpc.utexas.edu (Bersuker)
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Subject: MM for transition metal cpds
To: chemistry ^at^ ccl.net (Computational Chemistry List)
Date: Tue, 11 Jan 94 14:26:22 CST
Cc: cmao771 <-at-> charon.chpc.utexas.edu
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Dear Dr. Szilagyi:

I agree that problems should be solved with as small as possible efforts. If
your problem is solvable with the simple Hooke law, you are justified to do that
provided you proved that the results are reliable. But to my knowledge in many
(maybe most) cases, even if you are interested just in the nuclear configuration
it is impossible to avoid at least qualitative consideration of the electronic 
structure (see for example the effects of vibronic coupling in my book by
Plenum, 1984, or Springer, 1989). You mention the practical difficulties of
ab initio calculations for these systems (I agree with your reasoning), but
there is a variety of semiempirical methods which are much more reasonable and
adequate to the real physical and chemical problems. I am now working on a
relatively simple (practically acceptable) method of modeling TM systems that
includes the d-electron effects I suggested earlier.

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * 
Isaac B. Bersuker		 | E-mail: 
Dept. of Chemsitry	         | cmao771 \\at// charon.chpc.utexas.edu
Univeristy of Texas at Austin    | Vox: (512) 471-4671
Austin, TX 78712 	         | Fax: (512) 471-8696
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