Effect of Ge Additive on the Morphological and Physical Properties of Se100-xGex (x = 0, 1, 2, 4, 6, 10, 15 and 20) Chalcogenide System

Abstract

Ge additive chalcogenide materials have become more prevalent in contemporary optoelectronics. The present study utilizes the melt-quenching process for preparing Se-Ge chalcogenide glasses. For the examined system, submicron structural and physical characteristics are examined and described. X-ray diffraction spectra show no characteristic peaks, this indicates that the glassy compositions under investigation are amorphous. A further confirmation of the amorphous nature is provided by SEM. The physical properties of the compositions under examination namely cross-linking density (X), average coordination number (<r>), lone-pair electrons (L), mean bond energy (<E>), constraints (Nc), fraction of floppy modes (f), cohesive-energy (CE), glass transition temperature (T_g), electro-negativity (χ) as well as heat of atomization (H_s) have been deduced in regard to the influence of Ge content. Cohesive-energy is computed using CBA, while mean bond energy is obtained by chemical-bond ordering approach. Shimakawa's relationship was utilized to theoretically compute band gap of the system under investigation. Average single-bond energy, electro-negativity and cohesive-energy were used to analyse the results. A relationship between the mean coordination number and a variety of inferred physical characteristics is established.