The approximate coupled cluster doubles (ACCD) approximation is tested, both at the infinite-order level and at fourth order of many-body perturbation theory. It is found that in the presence of strong pair coupling, i.e. for most molecules, there is a substantial deviation between the ACCD and the
Further tests of the approximate double substitution coupled-cluster method
β Scribed by Clifford E. Dykstra; Shi-yi Liu; Michael F. Daskalakis; John P. Lucia; Mitsuo Takahashi
- Publisher
- Elsevier Science
- Year
- 1987
- Tongue
- English
- Weight
- 594 KB
- Volume
- 137
- Category
- Article
- ISSN
- 0009-2614
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