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arXiv · 2404.16236

Rigorous Formalization of Orbital Functionals: Addressing the Noninteracting $v$-Representability Problem

Neil Qiang Su
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Abstract

Functionals that explicitly depend on occupied, unoccupied, or fractionally-occupied orbitals are rigorously formalized using Clifford algebras, and a variational principle is established that facilitates orbital (and occupation) optimization as a formal implementation method. Theoretically, these methodologies circumvent the limitations encountered in the original Kohn-Sham and related methods, particularly when the interacting system's electron density does not match that of any noninteracting reference system. This work redefines orbital (and occupation) functionals from a novel perspective, positioning them not merely as extensions of traditional density functionals, but as superior, rigorous alternatives.

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Neil Qiang Su. 2024-04-24. Rigorous Formalization of Orbital Functionals: Addressing the Noninteracting $v$-Representability Problem. https://arxiv.org/abs/2404.16236

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