Using these results, we can interpret the magnetic susceptibility measurements between 150K and 25 K, spanning the range between χT ≈ 2 and χT ≈ 1 cm 3 K mol -1 , respectively (Figure ). Initially, we note that while the Curie law predicts an asymptotic magnetic susceptibility of χT ≈ 3, 1, and 0 cm 3 K mol -1 , for molecules in the ideal quintet, triplet, and singlet states, respectively, the experimental curve reflects the averaged contributions of all molecules/crystallites. Particularly, between cation I and cation II, the former exhibits variations in spin-state energies over the chosen temperature window while the latter maintains a stable S = 2 spin quantum number.