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arXiv · 1207.2775

Strong correlation in Kohn-Sham density functional theory

Francesc Malet·Paola Gori-Giorgi
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Abstract

We use the exact strong-interaction limit of the Hohenberg-Kohn energy density functional to approximate the exchange-correlation energy of the restricted Kohn-Sham scheme. Our approximation corresponds to a highly non-local density functional whose functional derivative can be easily constructed, thus transforming exactly, in a physically transparent way, an important part of the electron-electron interaction into an effective local one-body potential. We test our approach on quasi-one-dimensional systems, showing that it captures essential features of strong correlation that restricted Kohn-Sham calculations using the currently available approximations cannot describe.

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Francesc Malet, Paola Gori-Giorgi. 2012-11-13. Strong correlation in Kohn-Sham density functional theory. https://doi.org/10.1103/physrevlett.109.246402

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