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arXiv · 0909.3673

The Density Functional via Effective Action

Yi-Kuo Yu
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Abstract

A rigorous derivation of the density functional via the effective action in the Hohenberg-Kohn theory is outlined. Using the auxiliary field method, in which the electric coupling constant $e^2$ need not be small, we show that the loop expansion of the exchange-correlation functional can be reorganized so as to be expressed entirely in terms of the Kohn-Sham single-particle orbitals and energies.

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Yi-Kuo Yu. 2009-09-21. The Density Functional via Effective Action. https://arxiv.org/abs/0909.3673

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