Anisotropic distortions in Sb doped CePt4Ge12

[摘要] We investigated the local structure of the Sb doped skutterudite CePt4Ge12-xSbxusing the Extended X-ray Absorption Fine Structure Technique (EXAFS). As the concentration of Sb is increased the disorder around Ce increases rapidly, and for x = 3, the peak for the nearest neighbor (Ce-Ge) is no longer observed. In contrast, for the Pt site, the disorder of the nearest neighbors is small even for x = 3. Thus the distortions are anisotropic and appear to be mainly in the plane of the Ce-Ge bonds and Ge4rings. The increased disorder about Ce will decrease the lattice thermal conductivity at low temperatures, and likely is part of the reason for improved thermoelectric properties for the x = 1 sample.

[发布机构] Physics Department, UCSC, Santa Cruz; CA; 95064, United States^1;Physics Department, UCSD, San Diego; CA; 92093, United States^2;Materials Science and Engineering Program, UCSD, San Diego; CA; 92093, United States^3

[效力级别] 物理学 [学科分类] 材料科学（综合）

[关键词] Anisotropic distortion;Extended X-ray absorption fine structure techniques;Lattice thermal conductivity;Local structure;Low temperatures;Nearest neighbors;Sb-doped;Thermoelectric properties