Decoding short-range order in cation-disordered rocksalt materials using Metropolis non-negative matrix factorisation

Abstract

We present a methodology for accessing the cation short-range ordering (SRO) in disordered rocksalt (DRX) materials by decomposing their pair distribution function (PDF) pattern in terms of a set of basis PDFs, pre-determined via Metropolis non-negative matrix factorisation analysis. These basis PDFs, underpinned by structure modelling, point to specific SRO types that subsequently enable identification and quantification of their presence in the DRX structure. Rapid identification of the evolution of SRO addresses a key bottleneck in the analysis and understanding of high energy density characteristics of DRX materials.