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arXiv · 0704.1593

Orbital currents in the Colle-Salvetti correlation energy functional and the degeneracy problem

S. Pittalis·S. Kurth·S. Sharma·E. K. U. Gross
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Abstract

Popular density functionals for the exchange-correlation energy typically fail to reproduce the degeneracy of different ground states of open-shell atoms. As a remedy, functionals which explicitly depend on the current density have been suggested. We present an analysis of this problem by investigating functionals that explicitly depend on the Kohn-Sham orbitals. Going beyond the exact-exchange approximation by adding correlation in the form of the Colle-Salvetti functional we show how current-dependent terms enter the Colle-Salvetti expression and their relevance is evaluated. A very good description of the degeneracy of ground-states for atoms of the first and second row of the periodic table is obtained.

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S. Pittalis, S. Kurth, S. Sharma, E. K. U. Gross. 2007-07-31. Orbital currents in the Colle-Salvetti correlation energy functional and the degeneracy problem. https://arxiv.org/abs/0704.1593

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