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arXiv · 1809.10347

Quantifying Density Errors in DFT

Eunji Sim·Suhwan Song·Kieron Burke
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Abstract

We argue that any general mathematical measure of density error, no matter how reasonable, is too arbitrary to be of universal use. However the energy functional itself provides a universal relevant measure of density errors. For the self-consistent density of any Kohn-Sham calculation with an approximate functional, the theory of density-corrected density functional theory (DC-DFT) provides an accurate, practical estimate of this ideal measure. We show how to estimate the significance of the density-driven error even when exact densities are unavailable. In cases with large density errors, the amount of exchange-mixing is often adjusted, but we show this is unnecessary. Many chemically relevant examples are given.

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Eunji Sim, Suhwan Song, Kieron Burke. 2018-09-27. Quantifying Density Errors in DFT. https://doi.org/10.1021/acs.jpclett.8b02855

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