Cryst. Res. Technol. 39, No. 10, 873 – 876 (2004) / DOI 10.1002/crat.200410269 © 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim Crystal growth and characterization of the CdGaCrSe (4-X) S (X) system V. Sagredo* 1 , L. Betancourt 1 , L. M. de Chalbaud 1 , and G. E. Delgado 2 1 Laboratorio de Magnetismo en Sólidos, Departamento de Física, Facultad de Ciencias, Universidad de Los Andes, Mérida 5101, Venezuela 2 Laboratorio de Cristalografía, Departamento de Química, Facultad de Ciencias, Universidad de Los Andes, Mérida 5101, Venezuela Received 24 February 2004, accepted 20 April 2004 Published online 1 September 2004 Key words magnetic semiconductor, crystal growth, X-ray powder diffraction. PACS 81.10.Fq, 61.10.Nz Single-crystal of the CdGaCrSe (4-X) S (X) system (x = 0; 1; 2; 3; 4) were grown by the chemical vapour-phase transport technique. The crystals were obtaine by using CdCl 2 as transporting agent for the composition with x = 1, and CrCl 3 for those with x = 0; 2; 3 and 4. X-ray powder diffraction analysis indicated that some of the samples crystallizes in the tetragonal system with space group I-4 (CdGaCrSe 3 S , x = 1; CdGaCrSe 2 S 2 , x = 2), or in a cubic system with space group Fd-3m (CdGaCrSeS 3 , x = 3; CdGaCrS 4 , x = 4), however the sample of CdGaCrSe 4 (x = 0) crystallizes in rhombohedral system. Magnetic measurements show significant changes in the magnetic interactions behaviour probably due to the anionic substitutions. © 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim 1 Introduction During the past years diluted magnetic semiconductors (DMS) have been frequently investigated because of their magnetic, magneto-optical and magneto-transport properties arising from the presence of magnetic ions, mainly manganese ions in the cations sites [1,2]. Another family of semiconductors which shows very attractive structural characteristic and optical properties is the AB 2 X 4 . These ternary semiconductor compounds can be described, from the structural point of view, by one of the following three major structure types: the cubic spinel, the tetragonal defective zinc-blend and the rhombohedral ZnIn 2 S 4 -type structure. Recently, we have studied the crystallographic and magnetic aspects of the CdGa (2-2X) Cr (2X) S 4 [3-5] and CdGa (2-2X) Cr (2X) Se 4 [6] systems, respectively. In this work we report the crystal growth an X-ray powder diffraction characterization of the semiconducting system CdGaCrSe (4-X) S (X) with x = 0; 1; 2; 3; 4. Magnetic measurement of the compositions with x = 0; 1 and 4, are also reported. 2 Experiment Single crystals of the CdGaCrSe (4-X) S (X) system were grown by using the chemical vapour-phase transport technique. Previously, synthesis of the compounds was prepared by direct fusion of pure elements (purity 4N, 5N). Stoichiometric amounts of the powders were mixed into a sealed quartz ampoule (10 cm long and 8 mm internal diameter) under vacuum at 10 -5 Torr. One zone furnace was used. The compounds were then slowly heated from room temperature to 925 °C, (x = 0; 1) and to 1100 °C for all the others compositions. The heating ____________________ * Corresponding author: e-mail: sagredo@ula.ve