Microheterogeneity of Glassy Films of As2Sx (x<3) and Dendritic Texture on the Glasses

Abstract

Glassy films of As₂S _x with a continuous and optically uniform structure have been prepared by evaporation under the normal pressure in N₂ gas, x ranging from 2.7 to 2.9. The microheterogeneity and a dendritic texture of the films have been studied by means of optical microscope, X-ray diffraction, electron microscope and chemical etching. X-ray powder data for the dendritic texture did not fit any compound listed in the A.S.T.M. data file but are essentially identical with the synthesized As₂S₂ (or As₄S₄). Electron micrographs of surfaces etched with NaOH solution indicated the microheterogeneity of the glassy films. The present results suggest that the glass film is a microheterogeneous system consisting of an aggregate mixture of As₂S₃ and As₂S₂ (or As₄S₄).