Synthesis and spectral studies on some 3d metal complexes of a mesogenic ligand,N-(4'''-n-butylphenyl)-4-(4'-hexyloxybenzoate)salicylaldimine

摘要

A mesogenic (nematic) Schiffs base, N-(4'"-n-butylphenyl)-4-(4'-hexyloxy benzoate)salicylaldimine, Hbphbsal, (abbreviated as HL~1), was synthesized and its structure studied by elemental analyses, mass, NMR and IR spectra. A series of mesogenicon-mesogenic 3d metal complexes of the general formula, [M (L~1)2]n where M~(11) = Mn, Co, Ni, Cu and Zn has been prepared and structures were studied by various spectroscopic techniques. Spectral studies imply coordination of the ligand (HL1) as uni-negative bi/tri-dentate species to the metal ions, rendering overall geometry to distorted square planar (in case of Cu" complex) and octahedral geometry. The ESR spectra confirmed the presence of mixed copper-nitrogen and oxygen bonds in the chelate based on the g value. The Cu", Co" and Ni" complexes were found to be mesogenic (nematic) and their transition, melting and clearing points deviated from the ligand upon complexation.