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arXiv · 2602.16628

Stoichiometry Dependent Properties of Cerium Hydride: An Active Learning Developed Interatomic Potential Study

Brenden W. Hamilton·Travis E. Jones·Timothy C. Germann·Benjamin T. Nebgen
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Abstract

Cerium hydride has a variety of interesting properties, including a known lattice contraction and densification with increasing hydrogen content. However, precise stoichiometric control is not experimentally straightforward and {\it ab initio} approaches are not computationally feasible for many properties such as melting and low temperature diffusion. Therefore, we develop a machine-learned interatomic potential for cerium hydride that is valid for H to Ce ratios from 2.0 to 3.0. A query-by-committee active learning approach is used to develop the training set. Leveraging classical molecular dynamics simulations, we assess a range of properties and provide fundamental mechanisms for the trends with stoichiometry. A majority of the properties follow the trend of lattice contraction, being governed by the stronger lattice binding induced by adding octahedral atoms.

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Brenden W. Hamilton, Travis E. Jones, Timothy C. Germann, Benjamin T. Nebgen. 2026-02-18. Stoichiometry Dependent Properties of Cerium Hydride: An Active Learning Developed Interatomic Potential Study. https://arxiv.org/abs/2602.16628

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