Far-infrared investigation of ternary Ge–Se–Sb and quaternary Ge–Se–Sb–Te chalcogenide glasses

Abstract Chalcogenide glasses are remarkable materials for remote sensors, infrared imaging and infrared fibers due to their transparency in Far-infrared (IR) region. Far-IR absorption spectra of Ge 19 Se 81 − x Sb x ( x = 0, 4, 8, 12, 16, 17.2, 20) and Ge 19 − y Se 63.8 Sb 17.2 Te y (y = 0, 2, 4, 6, 8, 10) have been obtained in the range of 30–350 cm − 1 . Three possible bond arrangement approaches viz . chain-crossing model (CCM), random-covalent-network model (RCNM) and chemical bond approach (CBA) have been used to discuss the formation of bonds. Results are explained on the basis of GeSe 4 , GeSe 2 and SbSe 3 isolated structural units which have appeared in Ge–Se–Sb system while Se 6 Te 2 rings, GeTe 4 tetrahedron, GeTe 2 , GeSe 4 and GeSe 2 structural units have appeared for Ge–Se–Sb–Te system.