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arXiv · 1002.1351

Leading corrections to local approximations

Attila Cangi·Donghyung Lee·Peter Elliott·Kieron Burke
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Abstract

For the kinetic energy of 1d model finite systems the leading corrections to local approximations as a functional of the potential are derived using semiclassical methods. The corrections are simple, non-local functionals of the potential. Turning points produce quantum oscillations leading to energy corrections, which are completely different from the gradient corrections that occur in bulk systems with slowly-varying densities. Approximations that include quantum corrections are typically much more accurate than their local analogs. The consequences for density functional theory are discussed.

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Attila Cangi, Donghyung Lee, Peter Elliott, Kieron Burke. 2010-02-06. Leading corrections to local approximations. https://doi.org/10.1103/physrevb.81.235128

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