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arXiv · 1611.01443

Local density approximations from finite systems

Mike Entwistle·Matthew Hodgson·Jack Wetherell·Bradley Longstaff·James Ramsden·Rex Godby
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Abstract

The local density approximation (LDA) constructed through quantum Monte Carlo calculations of the homogeneous electron gas (HEG) is the most common approximation to the exchange-correlation functional in density functional theory. We introduce an alternative set of LDAs constructed from slablike systems of one, two and three electrons that resemble the HEG within a finite region, and illustrate the concept in one dimension. Comparing with the exact densities and Kohn-Sham potentials for various test systems, we find that the LDAs give a good account of the self-interaction correction, but are less reliable when correlation is stronger or currents flow.

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Mike Entwistle, Matthew Hodgson, Jack Wetherell, Bradley Longstaff, James Ramsden, Rex Godby. 2016-11-04. Local density approximations from finite systems. https://doi.org/10.1103/physrevb.94.205134

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