Comment on "Self-Averaging Stochastic Kohn-Sham Density-Functional Theory"

Jonathan E. Moussa; Andrew D. Baczewski

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arXiv · 1311.6576

Comment on "Self-Averaging Stochastic Kohn-Sham Density-Functional Theory"

Jonathan E. Moussa·Andrew D. Baczewski

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Abstract

In a recent Letter, Baer et al. present a stochastic method for Kohn-Sham density functional theory calculations. Their convergence criterion is the self-averaging total energy per electron, which requires a number of statistical samples that decreases with system size and enables a sublinear-scaling computational cost. However, the electron density, atomic forces, orbital energies, and many other physical quantities do not self-average, and this procedure causes their statistical errors to grow with system size. Convergence of non-self-averaging quantities requires that the number of samples be maintained with system size and is incompatible with a sublinear-scaling cost.

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Jonathan E. Moussa, Andrew D. Baczewski. 2014-04-12. Comment on "Self-Averaging Stochastic Kohn-Sham Density-Functional Theory". https://arxiv.org/abs/1311.6576

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