Dynamic correlations and possible diffusion pathway in the superionic conductor Cu_2-xSe.

ABSTRACT: The superionic conductor Cu_2-xSe has regained interest as a thermoelectric material owing to its low thermal conductivity, suggested to arise from a liquid-like Cu substructure, and the material has been coined a phonon-liquid electron-crystal. Using high-quality three-dimensional X-ray scattering data measured up to large scattering vectors, accurate analysis of both the average crystal structure as well as the local correlations is carried out to shed light on the Cu movements. The Cu ions show large vibrations with extreme anharmonicity and mainly move within a tetrahedron-shaped volume in the structure. From the analysis of weak features in the observed electron density, the possible diffusion pathway of Cu is identified, and it is clear from its low density that jumps betwe

SUBMITTER: Roth N 

PROVIDER: S-EPMC9980382 | biostudies-literature | 2023 Mar

REPOSITORIES: biostudies-literature