X-ray powder diffraction by p-type Cu2SnSe3, prepared by the vertical Bridgman–Stockbarger technique, shows that this material crystallizes in a monoclinic structure, space group Cc, with unit cell parameters a=6.5936(1) Å, b=12.1593(4) Å, c=6.6084(3) Å, and β=108.56(2)°. The temperature variation of the hole concentration p obtained from the Hall effect and electrical resistivity measurements from about 160 to 300 K, is explained as due to the thermal activation of an acceptor level with an ionization energy of 0.067 eV, whereas below 100 K, the conduction in the impurity band dominates the electrical transport process. From the analysis of the p vs T data, the density-of-states effective mass of the holes is estimated to be nearly of the same magnitude as the free electron mass. In the valence band, the temperature variation of the hole mobility is analyzed by taking into account the scattering of charge carriers by ionized and neutral impurities, and acoustic phonons. In the impurity band, the mobility is explained as due to the thermally activated hopping transport. From the analysis of the optical absorption spectra at room temperature, the fundamental energy gap was determined to be 0.843 eV. The photoconductivity spectra show the presence of a narrow band gap whose main peak is observed at 0.771 eV. This band is attributed to a free-to-bound transition from the defect acceptor level to the conduction band. The origin of this acceptor state, consistent with the chemical composition of the samples and screening effects, is tentatively attributed to selenium interstitials.

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The semiconductor compounds AgInVI2 (VI: S, Se, Te) crystallize in the chalcopyrite structure with space group I$\bar 4$2d. These compounds have received considerable attention because they show promising electrical and optical properties for solar cell devices. We report on a structural analysis of AgInTe2 polycrystalline samples by using the high‐energy powder diffraction technique. The experiments were performed at a pressure of P = 2.7 kbar at the DW11 station, LURE Orsay, France. The analysis of the experimental data was performed with EDX, DICVOL 91 and NBS‐AID‐93 programs. The structure of AgInTe2 was indexed in the tetragonal system with space group I$\bar 4$2d. The obtained lattice parameters were a = 6.262(3) Å and c = 12.897(2) Å. These results confirm the existence of a previously reported chalcopyrite phase for AgInTe2.