An open-shell coupled-cluster method for the direct calculation of excitation energies is presented. As a first test, applications to atomic Be and Ne are carried out, with exact inclusion of T, and T2 operators and lowest-order inclusion of T3. Quasicomplete model spaces are used. Two ionization p
Open-shell coupled-cluster method: Electron affinities of Li and Na
β Scribed by Uzi Kaldor
- Publisher
- John Wiley and Sons
- Year
- 1987
- Tongue
- English
- Weight
- 465 KB
- Volume
- 8
- Category
- Article
- ISSN
- 0192-8651
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β¦ Synopsis
The open-shell coupled-cluster method and the diagrams needed for its implementation are described. The method is applied to the electron ainities of Li and Na, which are calculated in two ways: as the ionization potential of the anions or as the energy of adding the second electron to the cations. The two schemes give essentially the same results, in very good agreement (c0.02 eV) with experiment. Threebody effects are negligible.
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