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A Rigorous Extension of the Kohn-Sham Equation for Strongly Correlated Electron Systems

Koichi Kusakabe
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Abstract

By introducing a set of auxiliary equations representing a many-body system, we have derived an extension of the Kohn-Sham scheme for the density functional theory. These equations consist of a Kohn-Sham-type equation determining single-particle orbitals and an eigen-value equation for an effective many-body problem. A variational method similar to the Kohn-Sham technique was utilized to derive effective interactions as well as effective potentials without artificial substitution of a Hubbard-type interaction and a mean-field correction in the energy functional. The second equation is described by an effective many-body Hamiltonian with both 2-body interactions and mean-field terms. Rigorous formulation of the extended Kohn-Sham equation is also given in accordance with the Hadjisavvas-Theophilou formulation. Our formulation can be interpreted as a way to define models of the strongly correlated electron systems, e.g. the Hubbard model

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BibTeXRIS

Koichi Kusakabe. 2001-03-05. A Rigorous Extension of the Kohn-Sham Equation for Strongly Correlated Electron Systems. https://doi.org/10.1143/jpsj.70.2038

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