Generalized gradient approximations to density functional theory: comparison with exact results

Claudia Filippi; Xavier Gonze; C. J. Umrigar

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Generalized gradient approximations to density functional theory: comparison with exact results

Claudia Filippi·Xavier Gonze·C. J. Umrigar

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Abstract

In order to assess the accuracy of commonly used approximate exchange-correlation density functionals, we present a comparison of accurate exchange and correlation potentials, exchange energy densities and energy components with the corresponding approximate quantities. Four systems are used as illustrative examples: the model system of two electrons in a harmonic potential and the He, Be and Ne atoms. A new ingredient in the paper is the separation of the exchange-correlation potential into exchange and correlation according to the density functional theory definition.

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Claudia Filippi, Xavier Gonze, C. J. Umrigar. 1996-07-07. Generalized gradient approximations to density functional theory: comparison with exact results. https://arxiv.org/abs/cond-mat/9607046

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