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Correlation energy and the use of Linnett-type orbitals in VB calculations for benzene and pyridine

✍ Scribed by C. Amovilli; R.D. Harcourt; R. McWeeny

Publisher: Elsevier Science
Year: 1991
Tongue: English
Weight: 469 KB
Volume: 187
Category: Article
ISSN: 0009-2614
DOI: 10.1016/0009-2614(91)80289-a

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✦ Synopsis

With two KekulC and three Dewar structures, Cooper et al. were able to recover 92% of the benzene r-electron correlation energy (the difference between the SCF energy and the I75-structure minimal basis set limit) by using symmetrically "distorted" AOs. Here it is shown that by using the asymmetric orbitals suggested by Linnett, 98.1% of the correlation energy can be obtained from four structures of pseudo-Kekule type. Similar results follow for pyridine and for a distorted benzene molecule used as a model in the study of reaction paths.

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