✦ LIBER ✦

An accurate numerical multicenter integration for molecular orbital theory

✍ Scribed by Hideaki Ishikawa; Kazuo Yamamoto; Kazumi Fujima; Misako Iwasawa

Publisher: John Wiley and Sons
Year: 1999
Tongue: English
Weight: 321 KB
Volume: 72
Category: Article
ISSN: 0020-7608
DOI: 10.1002/(sici)1097-461x(1999)72:5<509::aid-qua4>3.0.co;2-h

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✦ Synopsis

A powerful and accurate numerical three-dimensional integration scheme was developed especially for molecular orbital calculations. A multicenter integral is decomposed into the sum of single-center integrals using nuclear weight functions and calculated using Gaussian quadrature rules. The decomposed single-center integrands show strong anisotropy. With a careful selection of the Gaussian quadrature rule according to the anisotropy, it is possible to obtain an accuracy of 13 digits with a small number of integration points for the overlap integrals, normalization integrals, and molecular integrals for the hydrogen molecule.

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