Raman and infrared spectroscopic studies of GeGaAg sulphide glasses

• Published in: Materials science & engineering. B, Solid-state materials for advanced technology Solid-state materials for advanced technology, 1994, Vol.22 (2), p.191-200
• Main Authors: Julien, C., Barnier, S., Massot, M., Chbani, N., Cai, X., Loireau-Lozac'h, A.M., Guittard, M.
• Format: Article
• Language: English
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Disordered solids; Exact sciences and technology; Infrared and raman spectra and scattering; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Physics
• ISSN: 0921-5107; 1873-4944
• DOI: 10.1016/0921-5107(94)90243-7

Gallium sulphide forms stable glasses with GeS 2 over a wide range of composition, and in the same system complex materials are obtained by dissolving silver sulphide. In such glasses Ga 2S 3 acts as a co-former with GeS 2 whereas Ag 2S plays the role of modifier. Raman scattering and infrared absorption measurements have been carried out on the Ge 2S 4Ga 2S 3Ag 2S glass system. The structural arrangement of these glasses is studied as a function of the composition in the ternary glass-forming region. The vibrational assignment is made mainly in terms of bridging and non-bridging sulphur in the vitreous network. The tendency of gallium atoms to form GaS 4 tetrahedra forces germanium atoms to induce the formation of S 3GeGeS 3 structural groups due to the shortage of sulphur atoms. When Ag 2S is associated with Ge 2S 4Ga 2S 3 glasses, its defavors the edge-shared GeS 4 tetrahedra and contributes to the cohesion of corner-shared tetrahedra. When Ag 2S content increases, we observe a band located at low frequency that we have attributed to charge-coupled silver cation motion. A slight distortion of the tetrahedral groups is also seen from the vibrational features.