Magnetically diluted systems of dithiocarbamate complexes of the type 63,65Cu/[Ni(II)--Me(II)--Dtc] (Me = Zn, Cd, Hg; Dtc = MDtc (dimethyl-) or EDtc (diethyldithiocarbamate)), which model the structural heterogeneity on the local, molecular and supramolecular levels, have been prepared and studied by means of ESR and solid state 13C and 15N CP/MAS NMR spectroscopy.