Exchange functionals based on finite uniform electron gases

Pierre-François Loos

doi:10.1063/1.4978409

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arXiv · 1612.06022

Exchange functionals based on finite uniform electron gases

Pierre-François Loos

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Abstract

We show how one can construct \alert{a simple} exchange functional by extending the well-know local-density approximation (LDA) to finite uniform electron gases. This new generalized local-density approximation (GLDA) functional uses only two quantities: the electron density $\rho$ and the curvature of the Fermi hole $\alpha$. This alternative "rung 2" functional can be easily coupled with generalized-gradient approximation (GGA) functionals to form a new family of "rung 3" meta-GGA (MGGA) functionals that we have named factorizable MGGAs (FMGGAs). Comparisons are made with various LDA, GGA and MGGA functionals for atoms and molecules.

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Pierre-François Loos. 2016-12-19. Exchange functionals based on finite uniform electron gases. https://doi.org/10.1063/1.4978409

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