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On the role of single excitations in quasi-degenerate perturbation theory

✍ Scribed by Zoran Konkoli; Zhi He; Dieter Cremer

Publisher
Springer
Year
1997
Tongue
English
Weight
279 KB
Volume
96
Category
Article
ISSN
1432-2234

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For excitation energy calculations using quasidegenerate MBPT or coupled-cluster (CC) theory, the hitherto chosen strategy has been to have particle-hole (p-h) determinants forming the model space and to use standard formalisms origlnally developed for complete model spaces. In view of our recent an