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Optimized Effective Potentials in Finite Basis Sets

Tim Heaton-Burgess·Felipe A. Bulat·Weitao Yang
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Abstract

The finite basis optimized effective potential (OEP) method within density functional theory is examined as an ill-posed problem. It is shown that the generation of nonphysical potentials is a controllable manifestation of the use of unbalanced, and thus unsuitable, basis sets. A modified functional incorporating a regularizing smoothness measure of the OEP is introduced. This provides a condition on balanced basis sets for the potential, as well as a method to determine the most appropriate OEP potential and energy from calculations performed with any finite basis set.

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Tim Heaton-Burgess, Felipe A. Bulat, Weitao Yang. 2007-05-14. Optimized Effective Potentials in Finite Basis Sets. https://doi.org/10.1103/physrevlett.98.256401

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