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DOE OSTI · 21544624

Faddeev random-phase approximation for molecules

Degroote, Matthias·Van Neck, Dimitri·Barbieri, Carlo
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Abstract

The Faddeev random-phase approximation is a Green's function technique that makes use of Faddeev equations to couple the motion of a single electron to the two-particle-one-hole and two-hole-one-particle excitations. This method goes beyond the frequently used third-order algebraic diagrammatic construction method: all diagrams involving the exchange of phonons in the particle-hole and particle-particle channel are retained, but the phonons are now described at the level of the random-phase approximation, which includes ground-state correlations, rather than at the Tamm-Dancoff approximation level, where ground-state correlations are excluded. Previously applied to atoms, this paper presents results for small molecules at equilibrium geometry.

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74 ATOMIC AND MOLECULAR PHYSICSAPPROXIMATIONSATOMSCALCULATION METHODSCORRELATIONSENERGY LEVELSENERGY-LEVEL TRANSITIONSEQUATIONSEQUILIBRIUMEXCITATIONFADDEEV EQUATIONSFUNCTIONSGREEN FUNCTIONGROUND STATESMOLECULESPARTICLESRANDOM PHASE APPROXIMATION

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Degroote, Matthias, Van Neck, Dimitri, Barbieri, Carlo. 2011-04-15. Faddeev random-phase approximation for molecules. https://doi.org/10.1103/physreva.83.042517

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