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arXiv · 2509.07180

Effective Atom Theory: Gradient-Driven ab initio Materials Design

Justin Tahmassebpur·Brandon Li·Boris Barron·Héctor Abruña·Peter Frazier·Tomás Arias
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Abstract

We introduce Effective Atom Theory (EAT), a framework that transforms combinatorial materials design into a smooth, gradient-driven optimization within density functional theory (DFT). Atoms are represented as probabilistic mixtures of elements, enabling gradient-based optimizers to converge to a physically realizable material in about 50 energy evaluations -- far fewer than combinatorial optimization methods. Applied to Co-Cr-Ni-V oxides for the alkaline oxygen evolution reaction (OER), EAT leads to a final recommended composition of Co0.19Cr0.06V0.31Ni0.44O.

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Justin Tahmassebpur, Brandon Li, Boris Barron, Héctor Abruña, Peter Frazier, Tomás Arias. 2025-09-08. Effective Atom Theory: Gradient-Driven ab initio Materials Design. https://arxiv.org/abs/2509.07180

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