Synthesis, Electronic and IR Spectral Studies of Some Polymeric Cobalt(II), Nickel(II), Zinc(II) and Cadmium(II) Azido Complexes with Hydrazine

A series of polymeric cobalt(II), nickel(II), zinc(II) and cadmium(II) azido complexes with hydrazine of the type [M(N2H4)(H2O)(N3)Cl]n, [M(N2H4)(N3)2]n and [M(N2H4)2(N3)2]n have been prepared. These were characterized by elemental analyses, magnetic susceptibility measurements, electronic and IR spectra. The complexes are highly insoluble in polar and non polar solvents. All the complexes decompose with explosion at different temperatures between 100C to 200C. The magnetic moment and electronic spectral data for Co(II) and Ni(II) complexes suggest that the complexes have octahedral structure. The ligand-field parameters (10 Dq, B, , and LFSE) have also been calculated for all Co(II) and Ni(II) complexes which indicate a significant covalent character of M-L bonds. The IR spectra of the complexes show that the azide group and hydrazine molecule both act as bidentate bridging ligands in [M(N2H4)(H2O)(N3)Cl]n and [M(N2H4)(N3)2]n type complexes but the azide group is terminally bonded to metal in all [M(N2H4)2(N3)2]n type complexes.