HIGH-PRESSURE STRUCTURAL-CHANGES IN CHALCOGENIDE GLASSES

The pressure dependence of the first sharp diffraction peak has been studied for GeS//2 and As//2S//3 glasses. The shift of the peak position induced by hydrostatic compression is closely related to the macroscopic compressibility. The shift in glassy GeS//2 quantitatively corresponds to the change in the interlayer distance of the crystalline specimen under pressure. These observations indicate that the glasses consist of distorted layer molecules held together with van der Waals forces.