Synthesis and characterization of GeS2Ga2S3MCl2 (M=Ba, Cd) chalcohalide glasses

New chalcohalide glasses in the GeS2Ga2S3MCl2 (M = Ba, Cd) systems have been prepared. Physical properties have been characterized in terms of glass transition temperature, Tg (Tg=295-430 °C), thermal stability ΔT (ΔT=50-180 °C), thermal expansion coefficient, microhardness Hv and density d. Optical properties such as indices of refraction and optical bandgap are studied as a function of halide content. The GeGa-based chalcohalide glasses show optical bandgap extended towards shorter wavelengths. The evolution of glass structure due to MCl2 addition has been studied by Raman spectroscopy in the range 175-550 cm−1. Structural variations are related to those of physical properties.