Glass transition, thermal stability and glass-forming tendency of Ge-As-Se-S glassy systems

Ge 4 As 14 Se 82 , Ge 4 As 14 S 2 Se 80 , Ge 7 As 16 S 5 Se 72 , Ge 10 As 20 S 10 Se 60 , Ge 17.5 As 15 S 15 Se 52.5 , Ge 24 As 19 S 20 Se 37 , Ge 25 As 10 S 25 Se 40 , Ge 26 As 18 S 30 Se 26 , and Ge 33 As 17 S 35 Se 15 chalcogenide glass compositions were synthesized and molar percentage of element have been determined by energy-dispersive X-ray analysis. The parameters study the local structure (d, L), characterizing the chemical regularity (R) and glassy network topology (N co , f), the glass-forming ability (Hr), the thermal stability (Hʹ, S), the glass and crystallization regions (ΔT g-c ) of substances corresponding to different topological glass states (isostatic, rigid, elastic) are determined and physical features of the change of these parameters depending on the composition were studied according to X-ray diffraction, differential scanning calorimetry methods and Tanaka's two-dimensional layered structure approach.