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Approximate Brueckner orbitals in electron propagator calculations

✍ Scribed by J. V. Ortiz

Publisher: John Wiley and Sons
Year: 1999
Tongue: English
Weight: 154 KB
Volume: 75
Category: Article
ISSN: 0020-7608
DOI: 10.1002/(sici)1097-461x(1999)75:4/5<615::aid-qua27>3.0.co;2-t

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✦ Synopsis

Orbitals and ground-state correlation amplitudes from the so-called Brueckner doubles approximation of coupled-cluster theory provide a useful reference state for electron propagator calculations. An operator manifold with hole, particle, two-hole᎐one-particle and two-particle᎐one-hole components is chosen. The resulting approximate propagator may be regarded as an extension of the 2ph-Tamm-Dancoff w Ž .x approximation, third-order algebraic diagrammatic construction 2ph-TDA, ADC 3 and 3q methods. The enhanced versatility of this approximation is demonstrated through calculations on valence ionization energies, core ionization energies, electron detachment energies of anions, and on a molecule with partial biradical character, ozone.

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