Pilot numerical applications are reported of two recently formulated cluster expansion formalisms that generate connected effective Hamiltonians even for incomplete model spaces. Results are presented for prototype systems such as (a) the He atom, (b) the H2 molecule and (c) the He:+ ion. For He and
Open-shell coupled-cluster theory applied to atomic and molecular systems
โ Scribed by Azizul Haque; Uzi Kaldor
- Publisher
- Elsevier Science
- Year
- 1985
- Tongue
- English
- Weight
- 390 KB
- Volume
- 117
- Category
- Article
- ISSN
- 0009-2614
No coin nor oath required. For personal study only.
โฆ Synopsis
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 only exce?Iion bang neulral 0. IL is ConJectured that the omission of T, 1s responsible for this error.
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