introductionThe search for new organic nonlinear optical crystals has been of great interest because of their wide range of potential applications such as frequency doubling, optical switching, optical disk data storage, optical modulation, laser remote sensing and medical diagnostics. These materials attracting significant attention as they posses large nonlinear optical susceptibilities, ultrafast nonlinear response time, high laser damage threshold and scope for introducing desirable characteristics by multifunctional substitutions [1][2][3]
AbStrActSingle crystals of new organic nonlinear optical material urea L-valine were grown by slow eveporation solution growth technique at room temperature.Elemental compostion percentages were analysed using CHN study. Crystalline nature of the sample was confirmed by powder XRD. A functional group present in the crystal was identified using FT-IR spectral analysis. An optical transmittance study was also carried out for the crystal. Dielectric studies were performed with respect to temperature at various frequencies (50Hz-5MHz). Photoconductivity study reveals the negative photoconductivity nature of the crystal. Powder second generation efficiency of the crystal was studied using modified kurtz and perry technique. key words: Nonlinear, Powder X-ray diffraction, Optical, Dielectric, Photoconductivity, Single crystal XRD.years amino acids are playing a vital role in the nonlinear optical crystal growth. They individually exhibit nonlinear properties as they posses proton donor carboxyl acid (COO -) and proton acceptor amino (NH 3 ) group also in solid state they exist as zwitterions. Amino acid crystals play a major role in NLO applications such as L-valine, L-alanine,Lproline, L-leucine, L-histidine, L-arginine and L-phenylalanine. Worldwide urea and its derivatives are extensively used in crystal engineering and supramolecular chemistry for their flexibility in the synthesis of functional materials. Also for a long time it is used as a model system for crystals from solution growth and reference material in Powder SHG [3][4][5][6][7][8][9] .