Development and Applications of a Magnetism‐Aware General‐Purpose Atomic Cluster Expansion Potential for the Fe‐O‐H Ternary System

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.