DFT vs HF(CI)

From: Danilo Gonzalez <fgonzale -8 at 8- lauca.usach.cl>
Subject: DFT vs HF(CI)
Date: Mon, 27 Oct 1997 08:59:05 -0400

 Hi, folks!
 I wonder if you could help me with a question, related to DFT vs. HF
 calculations.
 Since DFT methods take into account, at least partially, correlation
 energies in molecules, a simple calculation of the HOMO-LUMO gap by a
 DFT method could be a good alternative to an HF/CI calculation, for the
 theoretical prediction of electronic transitions.  For example, am I
 right in expecting that the HOMO-LUMO gap of benzene, calculated by
 6-311G/B3LYP, would give me as good a  transition energy as, say a
 6-311G plus Configuration Interaction calculations (CIS) ?
 I will summarize and forward all answers.
 Thanks a lot!!,
 Danilo///
 --
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 Fernando Danilo Gonzalez N.
 University of Santiago de Chile
 Faculty of Chemistry and Biology, Computational Chemistry Lab.
 Casilla 40, Correo 33, Santiago, Chile    Fono: (562) 681 2575 Anexo:799
 E-mail : fgonzale -8 at 8- lauca.usach.cl            Fax   : (562) 681 2108
 URL    : http://quimbio.usach.cl/~danilo/
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