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arXiv · 1509.04089

Same-spin dynamical correlation effects on the electron localization

Stefano Pittalis·Alain Delgado·Carlo Andrea Rozzi
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Abstract

The Electron Localization Function (ELF) -- as proposed originally by Becke and Edgecombe -- has been widely adopted as a descriptor of atomic shells and covalent bonds. The ELF takes into account the antisymmetry of Fermions but it neglects the multi-reference character of a truly interacting many-electron state. Electron-electron interactions induce, schematically, different kind of correlations: non-dynamical correlations mostly affect stretched molecules and strongly correlated systems; dynamical correlations dominate in weakly correlated systems. Here, within an affordable computational effort, we estimate the effects of same-spin dynamical correlations on the electron localization by means of a simple modification of the ELF.

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Stefano Pittalis, Alain Delgado, Carlo Andrea Rozzi. 2015-09-14. Same-spin dynamical correlation effects on the electron localization. https://arxiv.org/abs/1509.04089

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