(Figure ). Upon lowering the temperature, a broad maximum is found in χT at around 100 K (χT = 8.6 cm 3 K mol -1 ), and below 8 K, χT drops drastically. To facilitate the interpretation of the magnetic properties of 2, we also plot in Fig. two times the χT value for 1 to which a constant value of 0.375 cm 3 K mol -1 is added to account for the contribution of the unpaired electron of the bridging ligand to the susceptibility (Figure ). The χT value for 2 is the same or slightly lower at room temperature compared to this reference value, but higher at all other temperatures. This observation is consistent with antiferromagnetic Co-radical interactions leading to a high-spin ferrimagnetic ground state with S = 5 2 .