DETERMINATION OF THE OPTICAL PSEUDOGAP IN DISORDERED PHASES WITH ARGYRODITE STRUCTURE

This paper is aimed to the determination of optical pseudogap values in phases with argyrodite structure by a simple method diffuse reflectance spectroscopy. Samples (Cu1-xAgx)7PSe6 (x = 0, 0.2, 0.3, 0.4, 0.6, 0.7, 0.9, 1.0) solid solutions were obtained form microcrystalline powders grinding agate mortar. The spectra samples studied spectral range 220–1400 nm (293 K) and analyzed using Kubelka-Munk function. It was found that for increase copper amount causes shift beginning absorption edge region higher energies. estimated combining Kubelka-Munch theory Tauc equation. established isovalent cationic substitution Ag+ → Cu+ leads monotonic decrease pseudogap, as result, compositional dependence which close linear. behavior can only be associated lattice parameters characterizes formation solutions.