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Molecular integrals in the generalized hylleraas–CI method

✍ Scribed by Yannan Lu; Zuqia Huang

Publisher
John Wiley and Sons
Year
1990
Tongue
English
Weight
522 KB
Volume
38
Category
Article
ISSN
0020-7608

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✦ Synopsis

Abstract

In the generalized Hylleraas–CI method, the original correlation factor r^v^~ij~ is multiplied by a Gaussian geminal. Using the approach of generating functions, the general formulas of molecular integrals in this method are derived over Cartesian Gaussian orbitals. From differentiations of the generating functions, the expanding length in the incomplete Gamma functions is reduced, and some cancellations presented in other approaches are avoided. Preliminary calculations for H~2~ and H~2~—H~2~ systems are carried out over STO‐3G basis. The results are encouraging.

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