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arXiv · 2510.15633

Atomic cluster expansion potential for the Si-H system

Louise A. M. Rosset·Volker L. Deringer
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Abstract

The silicon-hydrogen system is of key interest for solar-cell devices, including both crystalline and amorphous modifications. Elemental amorphous Si is now well understood, but the atomic-scale effects of hydrogenating the silicon matrix remain to be fully explored. Here, we present a machine-learned interatomic potential model based on the atomic cluster expansion (ACE) framework that can describe a wide range of Si-H phases, from crystalline and amorphous bulk structures to surfaces and molecules. We perform numerical and physical validation across a range of hydrogen concentrations and compare our results to experimental findings. Our work constitutes an advancement toward the exploration of large structural models of a-Si:H at realistic device scales.

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Louise A. M. Rosset, Volker L. Deringer. 2025-10-17. Atomic cluster expansion potential for the Si-H system. https://arxiv.org/abs/2510.15633

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