Effect of size of metal ion on MS4N2 chromophore: Synthesis, spectral and single crystal X-ray structural studies on (2,2′-bipyridine)bis(N-cyclohexyl-N-methyldithiocarbamato)M(II) (M = zinc, cadmium)

Two isomorphous complexes with the MS4N2 (M = Zn, Cd) chromophore have been synthesized. In the case of [Cd(S2CN(Me)Cy)2(bipy)], the N13CS2, methyl and C-1 (cyclohexyl) carbon signals 205.5, 36.7 and 64.42 ppm are shifted to higher frequency compared to [Zn(S2CN(Me)Cy)2(bipy)] 204.2, 35.6 and 63.1 ppm. The M-S and M-N bonds are longer and S-M-S angles are smaller in [Cd(S2CN(Me)Cy)2(bipy)] than that found in [Zn(S2CN(Me)Cy)2(bipy)].