Structure and physical properties of BaCuTeF

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) Å3; refinement residuals include Rp/wRp/RBragg (%)=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.