Growth, structural characterization and optical properties of CuGa0.8Mn0.2Se2.

Abstract

Polycrystalline sample of the compound CuGa0.8Mn0.2Se2 was grown by direct melting of the stoichiometric amounts of the constituent elements and subsequent controlled cooling, in vacuum quartz capsules and graphed by pyrolysis with acetone. Analysis of X-ray powder diffraction patterns at room temperature showed the tetragonal phase reported and the existence of secondary phases. The least squares method and a numerical calculation program were used to index the diffraction pattern and to calculate the network parameters of the studied composite. Differential Thermal Analysis (DTA) carried out on vacuum sealed samples allowed to establish phase transition temperatures. Transmission and reflection measurements were performed at room temperature with a fiber optic spectrophotometer. The energy gap was calculated from the absorption and verified measurements using a method that adjusts the measures of Reflectivity. The gaps are: (1.57 and 2.47) and V respectively.