Uniform Electron Gases. II. The Generalized Local Density Approximation in One Dimension

Pierre-François Loos; Caleb J. Ball; Peter M. W. Gill

doi:10.1063/1.4867910

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arXiv · 1401.0953

Uniform Electron Gases. II. The Generalized Local Density Approximation in One Dimension

Pierre-François Loos·Caleb J. Ball·Peter M. W. Gill

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Abstract

We introduce a generalization (gLDA) of the traditional Local Density Approximation (LDA) within density functional theory. The gLDA uses both the one-electron Seitz radius $\rs$ and a two-electron hole curvature parameter $η$ at each point in space. The gLDA reduces to the LDA when applied to the infinite homogeneous electron gas but, unlike the LDA, is is also exact for finite uniform electron gases on spheres. We present an explicit gLDA functional for the correlation energy of electrons that are confined to a one-dimensional space and compare its accuracy with LDA, second- and third-order Møller-Plesset perturbation energies and exact calculations for a variety of inhomogeneous systems.

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Pierre-François Loos, Caleb J. Ball, Peter M. W. Gill. 2014-02-26. Uniform Electron Gases. II. The Generalized Local Density Approximation in One Dimension. https://doi.org/10.1063/1.4867910

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