Variable-temperature (3 K to 10 K) magnetization data of thiolate complex 8 showed nesting of curves obtained at different fields, with saturation around 1.6 µB (Figure ]. An acceptable simulation of the remainder of the EPR spectrum was obtained using S = 3/2, g and D values derived from the magnetization data, and E/D of 0.20. D strain of 28 cm -1 (100% of D) was required to account for the broad spectrum. The necessity of large D strain to capture the overall shape of the spectrum indicates that a wide distribution of ZFS parameters were sampled in the spectrum. EPR spectra with similarly straindominated line shapes have been observed for other S = 3/2 iron complexes. In our system, the crystallographically-observed flexibility of the thiolate ligand may result in a mixture of conformers with varying ZFS. Based on the range of observed g values, the range of E/D for different conformers of 8 present in MeTHF is estimated to be between 0.1 and 0.2.