A new organic nonlinear optical (NLO) chalcone derivative viz.1- ( 4- methoxyphenyl )-3- (3,4 - dimethoxy phenyl ) - 2 - propene-1-one, has been synthesized by Claisen-Schmidt condensation method. The synthesized compound was purified by repeated recrystallization process. To confirm the identity of the synthesized compound, FTIR spectra was recorded and various functional groups present were identified. NMR spectra were recorded for structural identity and purity confirmation of the synthesized compound. Good quality single crystals were grown by solvent evaporation and slow cooling technique using acetone as solvent. The grown crystals were characterized by UV-Visible , differential thermal analysis and linear refractive index measurement. The hardness of the crystal was determined using Vicker's indentation method. The single crystal structure analysis of the crystal was performed and it is found that the crystal belongs to monoclinic system with space group P21. The powder second harmonic generation(SHG)frequency conversion efficiency of the crystal was determined using Nd: YAG laser(λ = 1064nm)and it is 15 times that of Urea.
Single crystals of antimony thiourea bromide with molecular formula Sb[CS(NH2)2]2Br3 (ATB) have been grown in gels at ambient temperature. Linear optical properties of this material such as refractive indices, birefringence and absorption characteristics were measured in the wavelength range 200 nm - 1400 nm. No dispersion of the birefringence was observed within the experimental accuracy. Optical second harmonic generation (SHG) of Nd:YAG laser (λ = 1.064 μm) has been observed for ATB crystal. In order to reveal the origin of non-linear optical property crystal structure of ATB has been determined. The non-linear optical property in ATB is due to the polar axis of the packing.