Subject: CCL:electronic correlation

From: Charles Martin <[email-masked]>
Date: Fri, 4 Apr 1997 15:31:37 -0800

Some more comments on non-dynamical and dynamical correlation:

	An equivalent way to view non-dynamical (or static)  
and dynamical correlation naturally arises within the framework
of very simple pi-electron theory such as the familiar PPP model.
The dynamical correlation enters into the pi-electron effective 
integrals (such as \alpha, \beta, and \gamma) through a good
empirical parameterization.  The static correlation is then just
the  pi-pi correlation included by diagonalizing the pi-CI Matrix.  

	From the ab initio point of view, the dynamical correlation
enters  into the pi-electron effective integrals via time-dependent 
(i.e. dynamical) many-body perturbation theory.  

-- 
========================================================
 ||     Charles H. Martin                            ||
 ||     2-004 Center for Science and Technology      ||
 ||     W. M. Keck Center for Molecular Electronics  ||
 ||     Department of Chemistry                      ||
 ||     Syracuse University                          ||
 ||     Syracuse, NY  13244                          ||
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