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Improved tensor-product expansions for the two-particle density matrix

Gábor Csányi·Stefan Goedecker·T. A. Arias
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Abstract

We present a new density-matrix functional within the recently introduced framework for tensor-product expansions of the two-particle density matrix. It performs well both for the homogeneous electron gas as well as atoms. For the homogeneous electron gas, it performs significantly better than all previous density-matrix functionals, becoming very accurate for high densities and outperforming Hartree-Fock at metallic valence electron densities. For isolated atoms and ions, it is on a par with previous density-matrix functionals and generalized gradient approximations to density-functional theory. We also present analytic results for the correlation energy in the low density limit of the free electron gas for a broad class of such functionals.

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Gábor Csányi, Stefan Goedecker, T. A. Arias. 2001-09-17. Improved tensor-product expansions for the two-particle density matrix. https://doi.org/10.1103/physreva.65.032510

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