A new sodalite-type compound, namely BaGe8As14 was synthesized via solid-state reactions and structurally characterized with single crystal X-ray diffraction (space group I43m). Vertex-sharing GeAs4-tetrahedra form beta-cages with additional Ge/As-mixed sites located slightly above or below the six-membered rings. The structure is similar to the borate mineral rhodizite. Barium atoms are disordered due to a slight shift off the centers of large beta-cages. This partially disordered structure together with a narrow bandgap of 0.43 eV in line with low resistivity (2 x 10(-2) omega cm), and a high carrier concentration (1.6 x 10(20) cm(-3)) at 300 K qualifies BaGe8As14 as a potential thermoelectric material.
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