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arXiv · 1807.05481

On-Top Density in the Nonlinear Metallic Screening and its Implication on the Exchange-Correlation Energy Functional

Yasutami Takada
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Abstract

In comparison with the accurate data on the on-top electron density n(0) in the proton-embedded electron gas with the density parameter r_s in the range 1-12 obtained by diffusion Monte Carlo (DMC) simulations, we have successfully constructed an alternative form of the exchange-correlation energy functional in the density functional theory by imposing the constraint due to the cusp theorem on the well-known Perdew-Burke-Ernzerhof (PBE) functional. Although PBE does not, our functional, referred to as the cusp-corrected PBE (ccPBE), reproduces the DMC data on n(0) in the entire range of r_s.

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Yasutami Takada. 2018-07-15. On-Top Density in the Nonlinear Metallic Screening and its Implication on the Exchange-Correlation Energy Functional. https://doi.org/10.1140/epjb/e2018-90111-0

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