Long-lived organic cation radical species, [1I]−and [2I]−, are formed when bimetallic CoIII or VV(O) complexes of a new binucleating ligand are oxidized by one electron. The VV(O) complex, [2I]−, has a total spin, ST, of 1/2, while the robust CoIII complex, [1I]−, has ST=3/2. The figure shows the spin arrangement within the complexes as deduced from combined EPR and SQUID measurements. The ferrimagnetic system, [1I]−, has both CoIII spin centers aligned in a common direction, an important step towards building ferromagnetic or ferrimagnetic network solids.