Characterisation of nickel(II) complexes of a substituted 2-acetylpyridine thiosemicarbazone by electronic and n.m.r. spectral studies

Summary Ni^II complexes of 1H-hexahydroazepine-1-thiocarboxylic acid-2-1-(2-pyridinyl)ethylidene] hydrazide (HL4A) of general formula Ni(L4A)X] (X=Cl, Br, I or NCS) have been synthesized and characterised by physical and spectroscopic methods. The molar conductivities show that all of the complexes are non-electrolytes. The terdentate character of the ligand in all cases is inferred from i.r. spectra, while the electronic spectra suggest planar geometries.