The Ag2S–GeS2–P2S5 system at 500 K

• Published in: Journal of solid state chemistry 2022-09, Vol.313, p.123340, Article 123340
• Main Authors: Berezniuk, О., Petrus, І., Olekseyuk, І., Smitiukh, О., Zamuruyeva, O., Nakhod, V.
• Format: Article
• Language: English
• Subjects: Chalcogenides; Crystal structure; Optical absorption coefficient; Phase equilibria; Solid solutions
• ISSN: 0022-4596; 1095-726X
• DOI: 10.1016/j.jssc.2022.123340

Phase equilibria in the quasi-ternary system Ag2S–GeS2–P2S5 at 500 K (227 °C) were investigated by physico-chemical analysis methods on 55 (plus 7 glass samples) alloys that were synthesized by direct single-temperature method. Phase diagram of the quasi-binary system Ag7PS6–Ag8GeS6 was also investigated. The limited solid solution ranges of the Ag7PS6 and Ag8GeS6 compounds are formed in the Ag7PS6–Ag8GeS6 system. The crystal structure of the two compositions was investigated by Rietveld method. The unit cell periods of the phases are: а = 1.5108 nm, b = 0.74609(7) nm, c = 1.0571(1) nm for Ag7.9P0.1Ge0.9S6, and а = 1.0403 nm for Ag7.1P0.9Ge0.1S6. Optical band gap was determined from the energy position of optical absorption edge at 293 K (20 °C) at a fixed value of the absorption coefficient α = 300 cm−1. [Display omitted] •Isothermal section of the quasi-ternary system Ag2S–GeS2–P2S5 at 500 K.•The Ag7PS6–Ag8GeS6 section.•The crystal structure of the phases Ag7.9P0.1Ge0.9S6 and Ag7.1P0.9Ge0.1S6.•Optical properties of glasses.