Role of Ge incorporation in the physical and dielectric properties of Se75Te25 and Se85Te15 glassy alloys

Abstract

The effect of Ge additive on the physical and dielectric properties of Se75Te25 and Se85Te15 glassy alloys has been investigated. It is inferred that on adding Ge, the physical properties i.e., average coordination number, average number of constraints and average heat of atomization increase but lone pair electrons, fraction of floppy modes, electronegativity, degree of crosslinking and deviation of stoichiometry (R) decrease. The effect of Ge doping on the dielectric properties of the bulk Se75Te25 and Se85Te15 glassy alloys has also been studied in the temperature range 300–350 K for different frequencies (1 kHz–5 MHz). It is found that, with doping, the dielectric constant e ′ and dielectric loss e ″ increase with increase in temperature and decrease with increase in frequency. The role of the third element Ge, as an impurity in the two pure binary Se75Te25 and Se85Te15 glassy alloys has been discussed in terms of the nature of covalent bonding and electronegativity difference between the elements used in making the aforesaid glassy systems.