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arXiv · 2607.15103

A fast summation method for the DFT-D3 dispersion correction

Victoria Valeeva·Cheuk Hin Ho·Mario Geiger·Franco Pellegrini·Gábor Csányi·Emine Kucukbenli·Christoph Ortner
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Abstract

The DFT-D3 dispersion correction is routinely added to machine learning force fields (MLFFs) trained on dispersion-deficient functionals such as PBE. Its environment-dependent pair coefficients, however, break the atom-centered separability that fast summation methods require, forcing practitioners either to truncate D3 or to accept a substantial slowdown. We introduce FourierD3, a method that uses a functional low-rank decomposition to restore this separability and enable particle-mesh evaluation in $O(N\log N)$ time without a real-space cutoff on the dispersion sum.

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Victoria Valeeva, Cheuk Hin Ho, Mario Geiger, Franco Pellegrini, Gábor Csányi, Emine Kucukbenli, Christoph Ortner. 2026-07-16. A fast summation method for the DFT-D3 dispersion correction. https://arxiv.org/abs/2607.15103

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