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arXiv · 2205.08177

Multilayer atomic cluster expansion for semi-local interactions

Anton Bochkarev·Yury Lysogorskiy·Christoph Ortner·Gábor Csányi·Ralf Drautz
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Abstract

Traditionally, interatomic potentials assume local bond formation supplemented by long-range electrostatic interactions when necessary. This ignores intermediate range multi-atom interactions that arise from the relaxation of the electronic structure. Here, we present the multilayer atomic cluster expansion (ml-ACE) that includes collective, semi-local multi-atom interactions naturally within its remit. We demonstrate that ml-ACE significantly improves fit accuracy compared to a local expansion on selected examples and provide physical intuition to understand this improvement.

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Anton Bochkarev, Yury Lysogorskiy, Christoph Ortner, Gábor Csányi, Ralf Drautz. 2022-05-17. Multilayer atomic cluster expansion for semi-local interactions. https://doi.org/10.1103/physrevresearch.4.l042019

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