ChemInform Abstract: Synthesis, Structure, and Thermoelectric Properties of Barium Copper Polychalcogenides with Chalcogen‐Centered Cu Clusters and Te^2‐₂ Dumbbells.

Abstract

BaCu5.72Se0.46Te6.54, BaCu5.93SeTe6, and BaCu5.92S0.986Te6.014 are synthesized from the elements (silica tubes, 663 K, 240 h) and characterized by single crystal XRD and DFT-based LMTO electronic band structure calculations. The compounds crystallize in the cubic space group Pm3 with Z = 1 in a hitherto unknown structure type comprising chalcogen-centered Cu atom clusters and dumbbells, while the Ba atoms are encapsulated in pentagonal Cu8Te12 dodecahedra. BaCu5.7Se0.6Te6.4 is a p-type semiconductor with moderate thermoelectric figure of merit, resulting from a combination of high Seebeck coefficient, low thermal conductivity, and low electrical conductivity. -(MAYASREE, O.; SANKAR, C. R.; CUI, Y.; ASSOUD, A.; KLEINKE*, H.; Eur. J. Inorg. Chem. 2011, 26, 4037-4042, http://dx.