Structure and physical properties of BaCuTeF

• Published in: Journal of solid state chemistry 2007-05, Vol.180 (5), p.1672-1677
• Main Authors: Park, Cheol-Hee, Kykyneshi, Robert, Yokochi, Alexandre, Tate, Janet, Keszler, Douglas A.
• Format: Article
• Language: English
• Subjects: BaCuTeF; BARIUM COMPOUNDS; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; COPPER COMPOUNDS; ELECTRIC CONDUCTIVITY; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; EV RANGE 01-10; Exact sciences and technology; FLUORIDES; INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; p-type degenerate semiconductor; Physics; Rietveld refinement; SEMICONDUCTOR MATERIALS; Single-crystal and powder diffraction; SPACE GROUPS; Structure of solids and liquids; crystallography; Structure of specific crystalline solids; Surface and interface electron states; TELLURIDES; TEMPERATURE RANGE 0273-0400 K; TETRAGONAL LATTICES; Thermal instruments, apparatus and techniques; Thermometry; X-RAY DIFFRACTION; X-ray diffraction and scattering
• ISSN: 0022-4596; 1095-726X
• DOI: 10.1016/j.jssc.2007.03.021

The compound BaCuTeF has been prepared by using high-temperature reaction methods, and its structure has been established via Rietveld refinement of powder X-ray diffraction data. It crystallizes in the tetragonal space group P4/ nmm (No. 129) with Z=2, a=4.4297 (1), c=9.3706 (1) Å, and V=183.87 (1) Å 3; refinement residuals include R p/w R p/ R Bragg (%)=6.72/4.42/5.72. A band gap of 2.3 eV is estimated from wavelength-dependent diffuse reflectance measurements. Room-temperature conductivities of pressed pellets are 6–8 S/cm, and variable-temperature Seebeck and electrical-conductivity measurements reveal p-type degenerate semiconductor behavior. The telluride fluoride BaCuTeF has been synthesized and structurally characterized through Rietveld refinement of X-ray diffraction data. It crystallizes in the tetragonal structure of LaCuOS. Optical and transport measurements have been used to establish the material as a degenerate p-type semiconductor with a band gap near 2.3 eV.