Single crystal growth of non-linear optical material tris-allylthiourea cadmium chloride (ATCC) single crystals has been investigated. The crystals were grown from aqueous solution by slow evaporation as well as by slow cooling technique. The influence of pH of the solution on the morphological and optical properties of the grown crystals was investigated. At pH 5-6, the crystals are elongated along a-axis. Bulk crystals have been grown from the optimized pH value of 3-4. The powder XRD analysis carried out on the grown crystals indicate no variation in lattice parameter values for different pH values of the growth solution. The FTIR analysis confirms the presence of sulfur to cadmium bonds in the complex for the crystals grown at different pH values of the solution. The functional groups present in the crystals were confirmed by Raman spectral studies. The mechanical property of the crystal grown at optimized pH was studied using Vicker's microhardness method. The change in the crystal morphology at pH values 3-4, 4-5 and 5-6 was attributed to the growth rate variations of prismatic planes at different pH values of the growth solution. Crystals grown at an optimized pH value (3-4) possess higher optical transmittance. The second harmonic generation conversion efficiency was measured qualitatively using Nd:YAG laser.

Semiconductors of II–VI group considered as interesting candidate for many researchers owing to its wide variety of applications in industries such as solar cells, solar selective coatings and optoelectronic devices. Chalcogenides of Cadmium received much attention due to its important structural feature, film composition, electronic and optical properties. The technique of low cost, low temperature electrochemical deposition has been employed to prepare Cadmium Selenide and Iron incorporated Cadmium Selenide thin films on transparent nature conducting substrates. The technique of X-ray diffraction has been used to identify crystalline nature and structural features of the deposited films. The method of Energy dispersive X-ray analysis has been used to find out the stoichiometric nature of the deposited films. The parameters viz., crystallite size, strain, dislocation density are estimated for the deposited films. The method of Ultraviolet-Visible spectroscopic measurements has been carried out to determine the optical properties of the deposited films. The deposited films found to exhibit band gap value in the range between 1.67 and 1.74 eV and the value of optical parameters refractive index and extinction coefficient, were estimated.

Allylthiourea complex crystals is an organometallic complex, a new nonlinear optical materials with high second harmonic generation effect. Tri-allylthiourea cadmium chloride and Tri-allylthiourea cadmium bromide are the promising nonlinear optical crystals belonging to this family. Both the crystals have been grown from an aqueous solution by slow cooling technique. The solubility and growth optimization of the grown crystals in terms of pH were analyzed and the influence of the different halogen atoms on the properties of as grown single crystals was studied by conducting various characterization techniques. Powder X-ray diffraction studies revealed that both the crystals are trigonal crystal structure with R3C space group. The spectroscopic properties were investigated by recording the Fourier Transform Infra Red and UV-Visible-NIR spectroscopy. Spectrocopic study confirmed the coordination of metal and red shift of the grown crystal. Nonlinear behavior of the as grown crystals was identified by Kurtz powder technique. Thermal and electrical properties of the as grown crystals were also analyzed by thermogravimetric and dielectric studies. Influence of the halogens on the growth as well as the properties were studied.