Generalized Kohn-Sham Density-Functional Theory via Effective Action Formalism

M. Valiev; G. W. Fernando

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arXiv · cond-mat/9702247

Generalized Kohn-Sham Density-Functional Theory via Effective Action Formalism

M. Valiev·G. W. Fernando

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Abstract

We present a rigorous formulation of generalized Kohn-Sham density-functional theory. This provides a straightforward Kohn-Sham description of many-body systems based not only on particle-density but also on any other observable. We illustrate the formalism for the case of a particle-density based description of a nonrelativistic many-electron system. We obtain a simple diagrammatic expansion of the exchange-correlation functional in terms of Kohn-Sham single-particle orbitals and energies; develop systematic Kohn-Sham formulation for one-electron propagators and many-body excitation energies. This work is ideally suited for practical applications and provides a rigorous basis for a systematic development of the existing body of first-principles calculations in a controllable fashion.

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M. Valiev, G. W. Fernando. 1997-02-27. Generalized Kohn-Sham Density-Functional Theory via Effective Action Formalism. https://arxiv.org/abs/cond-mat/9702247

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