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arXiv · 0902.1491

Non-empirical 'derivation' of B88 exchange functional

Peter Elliott·Kieron Burke
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Abstract

The B88 exchange energy density functional (created by Becke in 1988) is a crucial part of the most popular density functional in use today, B3LYP. B88 contains one empirical parameter which was fitted to Hartree-Fock exchange energies for the noble gas atoms. We show how local approximations to exchange become relatively exact under a very specific approach to the limit of large numbers, but that the usual gradient expansion does not. The leading corrections can be captured by generalized gradient approximations, producing a non-empirical derivation of the parameter in B88.

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Peter Elliott, Kieron Burke. 2009-02-09. Non-empirical 'derivation' of B88 exchange functional. https://arxiv.org/abs/0902.1491

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