Synthesis, characterization, optical absorption/fluorescence spectroscopy, and second-order nonlinear optical properties of aggregate molecular architectures of unsymmetrical Schiff-base zinc(II) complexes

This paper reports the synthesis and a detailed investigation in solution, through H-1 NMR, optical absorption, fluorescence spectroscopy and second-order nonlinear optical studies, on the structure and photophysical properties of a series of unsymmetrical alkoxy-derivatized Schiff-base Zn-II species bearing on one side an alkyl ammonium bromide as a Lewis base. Overall results suggest that these complexes are present in solution of dichloromethane as dimeric aggregates in which each molecular unit mutually interacts with another unit through intermolecular Zn center dot center dot center dot Br- interactions. This represents an alternative approach to control the supramolecular architecture of Lewis acidic, Schiff-base Zn-II complexes.