Synthesis and Thermal Study of Co (II), Ni (II), Cu (II) Mixed Ligand Complexes Using Histidine As Tridentate Ligand

Abstract

The mixed ligand complexes of Co (II), Ni (II) and Cu (II) with histidine (His.) and 8-hydroxyquinoline (Qui.) have been synthesized and characterized.The resulting complexes were characterized by vibrational and electronic spectral data, thermogravimetric studies , metal analysis and molar conductance measurements. The histidine acts as tridentate ligand, coordinating through the two nitrogen atoms of imidazole ring and the amino group and carboxylate oxygen whereas 8-hydroxyquinoline shows a bidentate nature and the coordination occurs through nitrogen of imine group and oxygen of phenol group. The experimental data suggest that a mononuclear octahedral structure with general formula [M (His.)(Qui.) H 2 O ] where M= Co (II), Ni (II) and [Cu (His.)(Qui.)H 2 O] .H 2 O, thermo gravimetric studies reveal the presence of coordinated water molecules in all complexes. The molar conductance measurements reveal non-electrolytic nature of complexes.