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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 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.