✦ LIBER ✦

Three-electron excitation in open-shell coupled-cluster theory

✍ Scribed by Azizul Haque; Uzi Kaldor

Publisher: Elsevier Science
Year: 1985
Tongue: English
Weight: 335 KB
Volume: 120
Category: Article
ISSN: 0009-2614
DOI: 10.1016/0009-2614(85)87054-8

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✦ Synopsis

The three-electron excitation operator TJ is included approximalely in the coupled-cluster method with single and double excilalions for open shells (CCSD). The resulting CCSD +T scheme incorporales all energy diagrams up to and including third order in the perturbation. All ten valence-shell energy difrerences of 0 and ils ions were calculated. They show significanl __ ekcts of TX and are within 0.1 eV OC the basis set limit.

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