Synthesis, quantum chemical studies, growth and characterization of an organic NLO single crystal: 4-Amino-(1-carboxymethyl) pyridinium chloride
The dual approach of quantum chemical studies and experimental characterizations of the organic NLO compound 4-Amino-(1-carboxymethyl)
pyridinium chloride (4A1CPC) were carried out for the first time. The molecular geometry of 4A1CPC was optimized by density functional theory (DFT) using B3LYP/6-311++G (d,p) basis set. The optimized structural parameters were compared with the experimental findings and discussed. The dipole moment (μ) and first hyperpolarizability (β) were calculated to predict the NLO behavior. The frontier molecular orbital (FMO), molecular electrostatic potential (MESP), mulliken atomic charge and thermodynamic properties were investigated to get a better insight of the molecular properties. Stability of the compound arising from hyper-conjugative interactions, intra-molecule rehybridization and charge delocalization within the molecule were analyzed using NBO analysis. Further 4A1CPC was synthesized and good quality single crystals were grown by SEST technique. Studies such as microanalysis and powder XRD were performed to ascertain material composition and phase respectively. The various characteristic functional groups were identified through FTIR spectroscopic analyses. The NLO efficiency was measured to be about 3.47 times greater than that of standard KDP. Thermal behaviors were explored by the simultaneous TG/DTA-DSC thermograms. The UV-Vis-NIR spectral data and fluorescence spectrum were recorded to explore the optical transmission and emission properties respectively. The dielectric properties (εr, tanδ and σac) were evaluated as a function of frequency at various temperatures. The photoconducting nature was analyzed through photoconductivity measurement. The Vicker’s microhardness test was performed at room temperature from which the mechanical stability was analyzed through the classical Meyer’s relation.