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arXiv · 1106.2744

Combination of many-body and density-functional theories

Dimitri Laikov
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Abstract

A framework for developing new approximate electronic structure methods is presented, in which the correlation energy of a many-electron system in the ground state is computed as in the single-reference second-order many-body perturbation theory but with the reference one-body Hamiltonian modified by additional (generally non-local) potentials which are universal functionals of the Hartree-Fock density. The existence of such functionals that reproduce the exact correlation energy justifies the search for approximate models which may overcome some important deficiencies of the traditional density-functional methods and also perform better than the usual low-order wavefunction methods.

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Dimitri Laikov. 2011-06-14. Combination of many-body and density-functional theories. https://arxiv.org/abs/1106.2744

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