SYNTHESIS, PROPERTIES AND SPECTROSCOPIC STUDIES OF COBALT(II) AND COBALT(III) COMPLEXES WITH PLANAR DITHIOXAMIDES

The complexes [Co(III)(LH2)3]X3 (LH2 = dithiooxamide,N-methyldithiooxa mide, N,N'-dimethyldithiooxamide; X = Cl, Br, I) and [Co(II)L]n have b een prepared. They were characterized by analyses, thermal techniques, magnetic susceptibilities and spectroscopic (ligand-field, C-13-NMR, FT-IR) methods. The vibrational analysis of the prepared complexes is given using NH/ND and CH3/CD3 isotopic substitutions. The neutral dith iooxamides exhibit a bidentate chelating S,S-coordination, while the d oubly deprotonated dithiooxamido anions act as bis-bidentate bridging S,N/N,S-ligands giving trans polymeric structures. The Co(III) complex es are octahedral with Co(III)S6 coordination spheres. A square planar geometry around Co(II) is assigned for the polymeric compounds.