Latent Ewald summation for machine learning of long-range interactions

Bingqing Cheng

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arXiv · 2408.15165

Latent Ewald summation for machine learning of long-range interactions

Bingqing Cheng

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Abstract

Machine learning interatomic potentials (MLIPs) often neglect long-range interactions, such as electrostatic and dispersion forces. In this work, we introduce a straightforward and efficient method to account for long-range interactions by learning a latent variable from local atomic descriptors and applying an Ewald summation to this variable. We demonstrate that in systems including charged and polar molecular dimers, bulk water, and water-vapor interface, standard short-ranged MLIPs can lead to unphysical predictions even when employing message passing. The long-range models effectively eliminate these artifacts, with only about twice the computational cost of short-range MLIPs.

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Bingqing Cheng. 2024-08-27. Latent Ewald summation for machine learning of long-range interactions. https://arxiv.org/abs/2408.15165

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