GVB]RP: A Reliable MCSCF Wave Function for Large Systems
نویسندگان
چکیده
Ž . ABSTRACT: We have developed a version of generalized valence bond GVB that overcomes the major weakness of the perfect pairing approximation without requiring a full transformation of the integrals at each step of the self-consistent orbital optimization. Ž . The method, called generalized valence bond]restricted pairing GVB]RP , describes properly the dissociation of up to triple bonds and provides smooth potential energy surfaces for most chemical reactions. The wave functions obtained are a good starting point for more sophisticated computational techniques. The applicability of the method is illustrated with a few simple examples including multiple-bond dissociations, transition states for symmetry allowed, symmetry forbidden, and radical reactions, as well as reactions at a transition-metal center. The cost of the method compares well with other self-consistent correlated techniques. Q 1999 John Wiley & Sons, Inc. Int J Quant Chem 73: 1]22, 1999
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