The open-shell coupled-cluster method IS applied to 21 SIZG of C. 0, O2 and their ION\_ Only two-electron excitations (T2) are taken into account Good agreement with experiment (better than 0.2 eV) is obtamed for the ten excitation enerwes and seven of the eight ionization potentials cakulaled. tie
Coupled-cluster approach for open-shell systems
✍ Scribed by Vladimir Kvasnička
- Publisher
- Elsevier Science
- Year
- 1981
- Tongue
- English
- Weight
- 303 KB
- Volume
- 79
- Category
- Article
- ISSN
- 0009-2614
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✦ Synopsis
The coupled-cluster approach IS generaked for open-shell systems, resultmg m a model InteractIon of hermltenn form. This theory represents a recurwe method for the simultaneous construction and evaluation of all posnble dlagrammatlc terms appearmg In a pertment many-body perturbntlon formahsm The coupled-cluster approach (CCA) of Coester [ 11, Kummel [2,3], CiZek [4,5] and Paldus [6-81.
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