Quantum critical benchmark for density functional theory

Paul E. Grabowski; Kieron Burke

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arXiv · 1408.2014

Quantum critical benchmark for density functional theory

Paul E. Grabowski·Kieron Burke

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Abstract

Two electrons at the threshold of ionization represent a severe test case for electronic structure theory. A pseudospectral method yields a very accurate density of the two-electron ion with nuclear charge close to the critical value. Highly accurate energy components and potentials of Kohn-Sham density functional theory are given, as well as a useful parametrization of the critical density. The challenges for density functional approximations and the strength of correlation are also discussed.

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Paul E. Grabowski, Kieron Burke. 2014-08-09. Quantum critical benchmark for density functional theory. https://arxiv.org/abs/1408.2014

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