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The Nd3+-doped lithium-zinc-phosphate glasses were prepared by means of conventional melt quenching method. X-ray Diffraction results were confirmed the glassy nature of the studied glasses. The physical parameters such as the density, molar volume, ion concentration, polaron radius, inter-ionic distance and field strength were calculated using different formulae. The absorption, transmittance and reflectance spectra of glasses were recorded in the wavelength range 190–1200 nm. Bonding of Nd3+ ions with surrounding ligands is found to be covalent. Dispersion parameters such as: single oscillator energy, dispersion energy, the ratio of carrier concentration to the electron effective mass and the lattice dielectric constant are determined. Electronic polarizability of the oxide ion and optical basicity of these glasses are calculated from the values of optical band gap. Effects of doping Nd2O3 on these properties are investigated and interpreted.

The Yb3+-doped Lithium-Zinc-Phosphate glasses were prepared by means of conventional melt quenching method. The elastic moduli of the entire vitreous range of this doped glass system have been measured by the ultrasonic pulse-echo technique at 4 MHz. The ultrasonic wave velocities, the bulk, shear, longitudinal and Young's moduli are found to be rather sensitive to the Yb2O3 wt% content. The infrared absorption spectra were recorded in the frequencies range 4000 to 400 cm–1. Absorption bands and mode attributions have been fully discussed. Absorption midband positions and intensities are found to be strongly dependent on Yb2O3 wt%. The optical absorption spectra in the visible and ultraviolet region were recorded at room temperature. The obtained results showed that a gradual shift in the fundamental absorption edge toward longer wavelengths occurred and it is observed that the values ofEopt. are decreased and ΔE increased with the increase of Yb2O3 wt% content.

The glass transition and the crystallization kinetics of Zn10Se90 glass by differential thermal analysis (DTA) technique under non-isothermal conduction were studied. The effective activation energies of the glass transition and the crystallization have been evaluated on the basses of the Kissinger and Matusita et al. approximations. Kinetic parameters of the crystallization process are significantly influenced by the heating rate. We have compared the experimental DTA with the calculated data curves for Zn10Se90 system using the Johanson–Mehl–Avrami (JMA) and Sestak–Berggren SB(M,N) models. Simulation results indicated that the SB(M,N) model is more suitable for describing the crystallization kinetics for the studied composition. Furthermore, the crystalline phases of annealed Zn10Se90 were characterized by X-ray diffraction. The surface morphology of the annealed samples was examined using scanning electron microscopy.

The Nd3+-doped lithium–zinc–phosphate glasses were prepared by means of conventional melt quenching method. X-ray diffraction results confirmed the glassy nature of the studied glasses. The physical parameters such as the density, molar volume, ion concentration, polaron radius, inter-ionic distance, field strength and oxygen packing density were calculated using different formulae. The transmittance and reflectance spectra of glasses were recorded in the wavelength range 190–1200 nm. The values of optical band gap and Urbach energy were determined based on Mott–Davis model. The refractive indices for the studied glasses were evaluated from optical band gap values using different methods. The average electronic polarizability of the oxide ions, optical basicity and an interaction parameter were investigated from the calculated values of the refractive index and the optical band gap for the studied glasses. The variations in the different physical and optical properties of glasses with Nd2O3 content were discussed in terms of different parameters such as non-bridging oxygen and different concentrations of Nd cation in glass system.

Bulk of ZnxSe100−x (x=10, 20 and 40 at%) was prepared by the usual quench melt technique. Thin films of these compositions were prepared by thermal evaporation. Differential thermal analyses (DTA) on powder samples under non-isothermal conditions show that the glass transition temperature Tg increased and crystallization temperature Tp decreased with increasing Zn content. The average particle size of the crystalline ZnSe phase deduced from X-ray diffraction (XRD) patterns show a decrease with increasing Zn content. These results were confirmed with the results obtained by scanning electron microscopy (SEM). The optical properties of ZnxSe100−x have been studied at a wavelength range (300–900 nm), and it was found that the optical band gap (Eg) increases with increasing Zn concentration in the ZnxSe100−x system. The results can be interpreted on the basis of the chemical bond approach proposed by Bicermo and Ovshinsky. The value of the extinction coefficient (k) decreases with increasing wavelength and Zn content. On the other hand, the optical energy gap (Eg) decreased with increasing the annealing temperature for Zn10Se90 thin films. These results can be interpreted by the Davis and Motte model.

Thin films of Zn 40 Se 60 were prepared by the vacuum thermal evaporation technique. The influence of annealed temperature on the structural and optical properties was investigated using the X-ray diffraction (XRD), scanning electron microscopy (SEM) and optical transmission. The XRD studies show that the as-deposited film is amorphous in nature, but the crystallinity improved with increasing the annealing temperature. Furthermore the particle size and crystallinity increased whereas the dislocation and strains decreased with increasing the annealing temperature. SEM studies showed that the annealing temperature induced changes in the morphology of the as-deposited sample. Various optical constant have been calculated for as-deposited and annealed films. The mechanism of the optical absorption follows the rule of direct transition. It was found that, the optical energy gap ( E g ) decreased with increasing the annealing temperature. These results can be interpreted by the Davis and Motte model. On the other hand the maximum value of the refractive index ( n ) is shifted toward the long wavelength by increasing the annealing temperature.