Structural characterization and low-temperature physical properties of p-type single-crystal K8Ga8.5Sn37.5 grown by self-flux method

• Published in: Journal of solid state chemistry Vol. 204; pp. 166 - 169
• Main Authors: Stefanoski, Stevce, Dong, Yongkwan, Nolas, George S.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Inc 01-08-2013; Elsevier
• Subjects: Anisotropy; Atomic structure; Clathrate; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Diffraction; Disorders; Exact sciences and technology; Flux method; Fluxes; Growth from melts; zone melting and refining; Materials science; Methods of crystal growth; physics of crystal growth; Minorities; Physics; Polyhedrons; Single crystal; Single crystals; Structure of solids and liquids; crystallography; Structure of specific crystalline solids; Thermoelectrics; Transport property; Clathrate; Thermoelectrics; Transport property; Flux method; Single crystal; Cubic lattices; Gallium; Space groups; Charge carriers; Transport properties; Electrical properties; Minority carriers; Physical properties; Clathrates; Thermoelectric materials; Electrical measurement; Monocrystals; Atomic displacements; Anisotropy; Transport processes; P type conductivity; X-ray diffraction analysis; Crystal growth from melts; Crystal structure
• ISSN: 0022-4596; 1095-726X
• DOI: 10.1016/j.jssc.2013.05.021

Single-crystal K8Ga8.5Sn37.5 was synthesized employing a self-flux method where Ga and Sn were used as fluxes. Single-crystal X-ray diffraction analyses revealed that this composition crystallizes in a cubic structure with the Pm3¯n space group (#223, a=11.9345(16)Å, V=1699.9(4)Å3, Z=1, and R/wR=0.0187/0.0382). A large dynamic disorder and anisotropic atomic displacement parameters were observed for K atoms inside the larger polyhedra in the crystal structure of K8Ga8.5Sn37.5. Electrical properties measurements indicate p-type conduction with onset of minority charge carrier conduction at temperatures above 270K.
Single-crystal K8Ga8.5Sn37.5 was synthesized via a double-flux method where Ga and Sn were used as fluxes. Large disorder for K inside the larger polyhedra in the crystal structure of K8Ga8.5Sn37.5 was observed. Measurements of the electronic properties indicate p-type conduction with the onset of minority charge carrier conduction at temperatures above 270K. [Display omitted]
•Single-crystal K8Ga8.5Sn37.5 synthesized for the first time, and fully structurally characterized.•Large disorder for K inside the larger polyhedra in the crystal structure of K8Ga8.5Sn37.5.•Electronic properties indicate p-type conduction with relatively low thermal conductivity.