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On the use of symmetry in first-order perturbed HF theory. II

✍ Scribed by Paolo Lazzeretti; Riccardo Zanasi

Publisher
John Wiley and Sons
Year
1979
Tongue
English
Weight
453 KB
Volume
15
Category
Article
ISSN
0020-7608

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✦ Synopsis

Abstract

A method is described whereby molecular symmetry is employed to reduce the number of two‐electron integrals in perturbed Hartree–Fock calculations of second‐order properties. The method is a generalization of the Dacre–Elder procedure. First‐ and second‐rank perturbing tensor operators are examined in the coupled HF approach to electric dipole polarizabilities, magnetic susceptibilities, quadrupole polarizabilities, and spin‐dopolar contributions to spin–spin coupling constants. The procedure sketched here permits a large saving of computer efforts, which is shown by some illustrative examples.

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