On the different coordination of NiII, ZnII and CdII cations in their model Schiff base complexes – Single crystal X-ray and solid state NMR studies

Abstract Three model metal complexes: Ni(NCS)L , Zn 2 (NCS) 2 L 2 and Cd 2 (NCS) 2 L 2 , consisting of the SCN − anion(s) and L = 2-[(2-dimethylaminoethylimino)-methyl]-phenolate, have been studied by X-ray diffraction and solid state NMR spectroscopy. The metal cations in these complexes have different coordination modes: Ni 2+ is almost square-planar, the Zn 2+ cation in Zn 2 (NCS) 2 L 2 is pentacoordinated, whereas Cd 2+ is penta- and hexacoordinated in [ Cd 2 (NCS) 2 L 2 ]. The different coordination of the metal cations influences the chemical shifts of the metal cations and also the nitrogen atoms. These chemical shifts can be correlated with the M–N and M–O bond lengths (M = Ni 2+ , Zn 2+ , Cd 2+ ).