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Multicomponent Density-Functional Theory for Electrons and Nuclei

Thomas Kreibich·Robert van Leeuwen·E. K. U. Gross
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Abstract

We present a general multi-component density functional theory in which electrons and nuclei are treated completely quantum mechanically, without the use of a Born-Oppenheimer approximation. The two fundamental quantities in terms of which our theory is formulated are the nuclear N-body density and the electron density expressed in coordinates referring to the nuclear framework. For these two densities coupled Kohn-Sham equations are derived and the electron-nuclear correlation functional is analyzed in detail. The formalism is tested on the hydrogen molecule $H_2$ and its positive ion $H_2^+$ using several approximations for the electron-nuclear correlation functional.

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Thomas Kreibich, Robert van Leeuwen, E. K. U. Gross. 2006-09-27. Multicomponent Density-Functional Theory for Electrons and Nuclei. https://arxiv.org/abs/cond-mat/0609697

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