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Updated: Aug 5, 2026

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Published on: February 5, 2022
Development and Applications of a Magnetism-Aware General-Purpose Atomic Cluster Expansion Potential for the Fe-O-H
Baptiste Bienvenu1, Mira Todorova1, Jörg Neugebauer1
1Max Planck Institute for Sustainable Materials, Düsseldorf, Germany.
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We develop and benchmark a general-purpose machine-learned interatomic potential for the Fe-O-H ternary system, based on the Atomic Cluster Expansion. Following our approach developed for the Fe-O system, magnetism is explicitly treated by the model in an Ising-like manner. This allows efficient incorporation of magnetic degrees of freedom, making the potential applicable to large-scale atomistic calculations. We demonstrate the capability of the model to accurately describe a wide range of properties and capture basic mechanisms underlying hydrogen-based reduction of iron oxides, interaction of water with iron and hydrogen embrittlement of metallic iron.
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