Chemical ordering and fragility minimum in Cu–As–Se glasses

Compositional dependence of thermal stability, glass-forming ability and fragility index in some Se–Te–Sn glasses

“…The coordination number of covalently bonded atoms in a glass is given by 8 − N rule, where N is the outer shell electrons (the column in the periodic table to which the element belongs). However, when metals atoms are added to a glassy material, this rule is violated and the metal atoms are found to be in higher coordination state [48]. For a multicomponent chain forming chalcogenide glassy system, the average coordination number is defined simply as the atoms averaged covalent coordination of the constituents.…”

Electrical switching and aluminium speciation in Al-As-Te glasses

“…The intermediate compositions 15 ≤ y ≤ 20 crystallized into Cu 3 AsSe 4 phase with amorphous background. Prolonged annealing (for 48 h) yields As 2 Se 3 phase for this intermediate range (15 ≤ y ≤ 20) [42,43]. Thermogravimetric analysis (TGA) showed weight loss for glasses with y ≥ 20.…”

Rapid quenching and glass formation in chalcogenide glasses: Preparation and properties of Ge–As–Te glasses over an extended composition ranges

“…Apart from RPT, another threshold is also predicted in chalcogenide at Z av = 2.67 based on the chemically ordered covalent network (COCN) model, called the chemical threshold (CT) [15,[25][26][27][28]. At the CT, the system achieves maximum chemical ordering as the bonding becomes completely heteropolar.…”