Growth and Characterization of a Non-linear Optical Crystal: Thiourea Added L-histidine Crystals

Single crystal of Thiourea added L-Histidine (TULH) have been grown by slow evaporation solution growth technique. Good optical quality single crystal of dimension up to 34x5x8mm 3 have been obtained. To identify the morphology and structure, the as grown crystals were subjected to single crystal and powder x-ray diffraction analysis. The different mode of vibrations present in the crystal was identified with FT-IR spectra. The optical transmission spectrum and Second Harmonic Generation (SHG) have been studied to find its linear and Non-linear properties. It is observed that the crystal has transparency window from 350nm to 1100nm and its energy gap (Eg) found to be is 3.9eV. Second Harmonic Generation studies reveal that the crystal is suitable for frequency conversion application. The thermal stability of the grown crystal was found by thermogravimetric (TG) and differential thermal analysis (DTA). Mechanical property of the crystal carried out by Vicker’s Micro hardness tests shows that TULH crystal is soft in nature. Photoconducting measurement reveals the positive Photoconducting nature of the as grown crystal.