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arXiv · 1404.1663

Correlation energy expressions from the adiabatic-connection fluctuation-dissipation theorem approach

János G. Angyán·Ru-Fen Liu·Julien Toulouse·Georg Jansen
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Abstract

We explore several random phase approximation (RPA) correlation energy variants within the adiabatic-connection fluctuation-dissipation theorem approach. These variants differ in the way the exchange interactions are treated. One of these variants, named dRPA-II, is original to this work and closely resembles the second-order screened exchange (SOSEX) method. We discuss and clarify the connections among different RPA formulations. We derive the spin-adapted forms of all the variants for closed-shell systems, and test them on a few atomic and molecular systems with and without range separation of the electron-electron interaction.

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János G. Angyán, Ru-Fen Liu, Julien Toulouse, Georg Jansen. 2014-04-07. Correlation energy expressions from the adiabatic-connection fluctuation-dissipation theorem approach. https://doi.org/10.1021/ct200501r

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