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A series of stable and transparent glasses with the composition 59B 2 O 3-10Na 2 O-(30 − x) CdO-xZnO-1CuO (0 ≤ x ≤ 30) (where x = 0, 7.5, 15, 22.5, and 30 mol%) were prepared by conventional melt-quenching technique. These glasses were characterized using X-ray diffraction (XRD), Fourier-transform infrared (FTIR) and Raman spectroscopes, differential scanning calorimetry (DSC), optical absorption, and electron paramagnetic resonance (EPR). XRD and DSC analysis confirmed the glassy nature of the prepared samples. The physical properties such as density (ρ), molar volume (V m), oxygen packing density (OPD), and the molar volume of oxygen (V o) were calculated and discussed. FTIR and Raman studies showed that the glass network consists of BO 3 and BO 4 units in various borate groups. From DSC, it was found that the glass transition temperature (T g) varies nonlinearly with the addition of ZnO content in place of CdO. Both EPR and optical absorption results have confirmed that the Cu 2+ ions are in octahedral coordination with a strong tetrahedral distortion. The changes in various spectroscopic properties of Cu 2+ ions in the glasses such as spin-Hamiltonian parameters () and bonding coefficients (α 2 , β 1 2 , and β 2) were understood with the help of FTIR and Raman studies.

The Chemical Bath Deposition Method (CBD) was employed for deposition of Cd 1-x Zn x S (x = 0.0, 0.2, 0.4, 0.6, 0.8, 1.0) thin films. The chemically deposited Cd 1-x Zn x S thin films were characterized by using UV-Visible spectrophotometer. Transmission spectra show the blue shifting of absorption edge as the Zn content increased. The x = 0.8 composition shows maximum 78 % transmittance. The reflection in the blue portion of the incident spectrum was decreased as the Zn content increased. The (αhν) 2 versus photon energy (hν) curves shows tuning of band gap with Zn content. The observed band gap was 3.9 eV in the x = 0.8 composition. The effect of composition on refractive index, absorption index and other optical dispersion parameters were also investigated. The calculated values of average excitation energy E o approximately obey the empirical relation (E o =1.2 E g) obtained from single oscillator model.

Monophasic nanocrystals of rare earth gadolinium (Gd 3+) ion doped nickel-cobalt ferrite, Ni 0.5 Co 0.5 Gd y Fe 2−y O 4 (y = 0.00, 0.025, 0.050, 0.075, 0.100 and 0.125) have been synthesized by l-ascorbic acid assisted sol-gel auto-ignition process. Thermogravimetric and differential scanning calorimetry, X-ray diffraction, Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM) with selected area electron diffraction (SAED) patterns, ultraviolet-visible spectrophotometry and vibrating sample magnetometer were employed to characterize the microstructure, optical and magnetic properties. Structural investigations verified the presence of cubic spinel phase short of any contamination peak. The average crystallite size was seen in nano-regime dimensions and well confirmed by TEM results. SAED patterns showed bright and intense ring of (311) plane revealed the establishment of spinel ferrite nanocrystals. Lattice constant (a) increases steadily with the rise in Gd 3+ content following the Vegard's law. FTIR spectra confirmed the creation of spinel ferrite structural geometry. Saturation magnetization (M s) and a remanence magnetization (M r) decreased from 29.77 to 20.78 emu/g and 21.62 to 15.79 emu/g, respectively, with increasing the Gd 3+ content. However, coercivity (H c) is significantly increased. The highest value of H c = 1132 Oe was found for y = 0.075 sample. The reduction in M s values can be justified owing to the replacement of Fe 3+ existing at the octahedral [B]-sites by the Gd 3+ ions which is paramagnetic at room temperature. The elucidation of magnetic parameters with Gd 3+ doping was attributed to the discrepancy of anisotropy constant, the paramagnetic nature of Gd 3+ and crystallite size effect.