Complex impedance spectroscopic data were acquired on single crystals of the morphotropic phase boundary composition of 0.68Pb(Mg1/3Nb2/3)O3-0.32PbTiO3 over a wide range of temperatures (25–525 °C) and frequencies 1 kHz–1 MHz. This study takes advantage of plotting ac data simultaneously in the form of impedance and modulus spectroscopic plots. This permits the easy interpretation of microscopic processes responsible for the measured ac response. Frequency explicit plots of imaginary components of impedance and modulus exhibit Debye-like peak shapes. The data for ac conductivity were computed from the impedance data and the activation energy for conduction at different frequencies was determined. Cole–Cole diagrams were plotted and these indicate the presence of a single relaxation process. The relaxation times determined from these plots followed an Arrhenius law, and the activation energy for relaxation was found to be 1.2 eV. The ac conductivity data was found to obey Jonscher’s universal power law and resulted in a value of the exponent “n”=0.95.

Glycine Lithium Sulphate (GLS) is one of the potential materials for Non-linear optical property applications. Single crystals of Glycine Lithium Sulphate (GLS) with very high degree of transparency were grown from aqueous solution by slow evaporation technique. Single crystal X-ray diffraction analysis reveals that the crystal belongs to orthorhombic system with the space group Pna2 1. The density measurements were carried out by both theoretical and experimental methods. The optical absorption study reveals the transparency of the crystal in the entire visible region and the cut off wavelength has been found to be 350 nm. The dependence of extinction coefficient (K) and refractive index (n) on the absorption has also been reported. The mechanical properties were studied using Vickers microhardness tester. The dielectric studies were also reported for grown crystals. The photoconductivity reveals the negative nature of the photocurrent in these crystals.

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