✦ LIBER ✦

A diagrammatic valence bond method for configuration interaction calculations in atoms and molecules

✍ Scribed by S. Ramasesha

Publisher: Elsevier Science
Year: 1986
Tongue: English
Weight: 321 KB
Volume: 130
Category: Article
ISSN: 0009-2614
DOI: 10.1016/0009-2614(86)80250-0

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✦ Synopsis

A diagrammatic valence bond method based on Rumer-Pauling rules for configuration interaction calculations is described. The advantages of this method are that it is simple and flexible and is expected to be computationally efficient as the basis functions can be coded as increasing integers. Evaluation of Hamiltonian matrix elements; involves simple bit manipulations and binary searches. The basis, being represented pictorially, should also help in utilizing spatial symmetries for further blockdiagonalizing the Hamiltonian matrix. The eigenfunctions of the Hamiltonian can also be used to compute matrix elements between different electronic states.

* Communication No. 374 from the Solid State and Structural

Chemistry Unit.

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