Modeling Short-Range Order in High-Entropy Cation-Disordered Rocksalt-Type Cathodes

Understanding short-range order (SRO) in high entropy (HE) ceramics is essential for the compositional and structural design of the materials. Here, a Short-Range Order Swapping (SROS) method is developed that constructs atomistic SRO models efficiently using a descriptor-based swapping algorithm. Through feature selection and Bayesian optimization, the approach markedly reduces computational demands compared to conventional approaches that involve explicitly fitting many-body interactions, while preserving high accuracy, as experimentally validated by neutron pair distribution function data. The SROS method is applied to investigate cation-disordered rock-salt (DRX) materials, promising candidates for next-generation high-energy-density cathodes with high-level structural complexity. Using the structures generated by the SROS method, it elucidates how configurational entropy suppresses SRO in HE-DRX, which contributes to reduced disordering temperatures, enhanced diffusion dynamics, and minimized structural and volumetric changes. The SROS method holds potential for broader applications in other HE ceramic crystal systems characterized by long-range disorder and SRO.