DC magnetic susceptibility (χ) and magnetisation (M) measurements of 1 were taken in the T = 300-2.00 K, B = 0.1 T and T = 2.0-10 K and B = 0.5-9.0 T temperature and field ranges, respectively. These are plotted as the χT product versus T and M versus B in Fig. . The T = 300 K value of χT = 43.2 cm 3 K mol -1 is equal to the value expected for sixteen non-interacting S = 3/2 Co II ions with g = 2.40. Upon cooling the χT value decreases slowly to ~41.7 cm 3 K mol -1 at 38 K before rising sharply to a maximum of ~52.8 cm 3 K mol -1 at T = 6 K, and then falling to ~10.9 cm 3 K mol -1 at T = 2 K. The initial drop in χT is due to the magnetic anisotropy of the octahedral Co II ions, while the increase at low temperature is due to weak ferromagnetic interactions. The drop in value between 6-2 K is most likely due to intermolecular antiferromagnetic interactions. This behaviour is similar to that observed for the pyridone-stabilised [Co12] wheel. The M vs B data is in agreement with this interpretation, with the magnetisation increasing rapidly with increasing field, not saturating and reaching a value of M = 33.4 µB at T = 2 K and B = 9 T. The ferromagnetic exchange in 1 is consistent with magneto-structural correlations developed for O-bridged Co II clusters where the sign and magnitude of the interaction is dictated by the Co-O-Co angle, with the exchange becoming more ferromagnetic with decreasing angle. Here, the Co-O-Co angles are all ≤ 99.5° and are therefore expected to mediate weak ferromagnetic exchange.