Subject: Computing Bond Strengths

From: [email-masked] (Charles Martin)
Date: Mon, 23 May 1994 11:07:18 -0600 (CDT)

There has been some discussion about computing bond stregnths, and I 
am wondering if anyone has tried or has some thought about
the following:

Using ab initio calculations, one can compute absolute energies 
with a high level correlated calculation, like Hartree Fock plus 
perturbation theory (MP2, MP4, etc.) Clearly one can calculate
dissociation energies just by strecthing the bond.  On the other
hand, I can imagine reformulating the MP2/MP4 equations so that
the bond energies woulod appear directly.  For example, recently papers
have appeared by Aml\"of (Chemical Physics Letters, 1991 or 1992, I think) 
that describe reformulating the MP2/MP3/... equations using a
loclaized basis.  I believe that the intetnt of these papers was to
simply speed up the MP2 computation, but I think that accurate bond energies
could also be computed if the energy compoents could be cleanly
seperated into bond terms, bond-bond interactions, etc.  

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Charles H. Martin

email: [email-masked]

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