Growth, experimental and theoretical analysis of physical properties of an organic NLO 2Methylimidazole l-Tartrate (2MILT) crystal

Abstract

Single crystals of organic salt 2-Methylimidazole l-Tartrate (2MILT) have been grown by slow evaporation method from ethanol and water solution. Single crystal and Powder X-ray analysis confirms that the crystal structure belongs to monoclinic system. The quantum chemical calculation has been carried out with DFT function in ground state with Gaussian analysis software. The various parameters have been obtained and compared with experimental parameters. Presence of all functional group is in right composition have been confirmed through FTIR-ATR spectroscopy. The same has been confirmed with FT-Raman response and theoretical calculated values. The title compound shows good UV–Visible transmission of more than 80% throughout with cut-off wavelength of 245 nm. The HOMO-LUMO analysis has been also carried out with Gaussian. Good crystalline quality of 2MILT grown crystals have been confirmed through further analysis like Urbach energy, Extinction coefficients and other parameters. The salt decomposes in single phase at around 210 °C. The dielectric parameters like dielectric constant, dielectric loss, AC conductivity and Joncher's parameters have been investigated. Being Nonlinear Optical (NLO) crystal, the SHG of 2MILT have been found 1.81 times that of same particle size of KDP. The higher laser damage threshold of 10.2 GW/cm2 ensures the compatibility of crystal for NLO applications.