Crystal structure, thin film preparation, theoretical and experimental study the nonlinear optical properties of a novel copper complex

Abstract A novel metal-organic complex: bis(imidazole)-bis(isothiocyanato)-copper(II) ((C3H4N2)2Cu(NCS)2) has been synthesized, its crystal structure has been determined by means of X-ray single crystal diffraction. The copper(II) ion is four coordinated with the four nitrogen atoms in a square planar environment, short contacts of C-H···C and S‾···Cu2+ leading to the formation of a two-dimensional (2D) supramolecular plane structure parallel ab plane. Its crystal thin film were prepared using in-situ crystallization methods on quartz substrates. The surface morphology of the thin film were studied by atomic force microscopy (AFM). The nonlinear optical (NLO) properties of the thin film were investigated by using closed aperture Z-scan technique with 20 picosecond (ps) pulses at wavelength 532 nm. Time-dependent density-functional theory (TDDFT) with the basis set LanL2DZ were used in theoretically computing the frontier molecular orbitals (FMO) and molecule′s second hyperpolarizability γ value.