Growth, Spectral, Optical and Thermal Characterization of NLO Organic Crystal – Glycine Thiourea

Optical quality single crystals of glycine thiourea (GT), a new organic nonlinear optical (NLO) crystal, were grown from aqueous solution by slow evaporation method. Solubility of GT was determined at various temperatures. Single crystal X-ray diffraction studies indicate that GT crystallizes in the monoclinic crystal system. Various diffracting planes of the grown crystal were identified from the powder X-ray diffraction study. The various functional groups of molecules present in GT were identified from FT-IR studies. The elemental analysis confirmed the stoichiometry of the compound. Optical characterization of the crystal shows the cut off wavelength near the UV region. Thermal stability and melting point of the grown crystal were found by thermal analyses. The powder second harmonic generation test of GT revealed its relative NLO efficiency is approximately 0.5 times that of potassium dihydrogen orthophosphate. The mechanical strength of the grown crystal is estimated by Vicker’s hardness test.