Structure and physical properties of BaCuTeF

摘要

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 P4mm (No. 129) with Z = 2, a = 4.4297 (1), e = 9.3706 (1) angstrom, and V = 183.87 (1) angstrom(3); refinement residuals include R-p/wR(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. (c) 2007 Elsevier Inc. All rights reserved.