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arXiv · 2108.01232

Exposing minimal composition of Kohn-Sham theory and its extendability

H. Nakada
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Abstract

Reducing the many-fermion problem to a set of single-particle (s.p.) equations, the Kohn-Sham (KS) theory has provided a practical tool to implement \textit{ab initio} calculations of ground-state energies and densities in many-electron systems. There have been attempts to extend the KS theory so that it could describe other physical quantities, or it could be applied to other many-fermion systems. By generalizing and reformulating the KS theory in terms of the 1-body density matrix, we expose the minimal composition of the theory that enables the reduction of the many-fermion problem to the s.p. equations. Based on the reformulation, several basic issues are reconsidered. The $v$- and $N$-representabilities for the KS theory are distinguished from those for the Hohenberg-Kohn theorem. Criteria for the extendability of the KS theory are addressed.

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H. Nakada. 2021-08-03. Exposing minimal composition of Kohn-Sham theory and its extendability. https://doi.org/10.1088/1402-4896%2Facf4d0

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