Theoretical Study of the Magnetic Behavior of Ferric Wheels

Calculations of exchange coupling constants (J) based on density functional theory for eight complete, nonmodeled ferric wheels have been performed, and a comparison with the values obtained from magnetic susceptibility data is presented. The calculated J values obtained with a generalized‐gradient approximation (GGA) functional are in good agreement with the experiment probably because the inclusion of pseudopotentials partially compensates the overestimation of the spin delocalization. The magnetostructural correlation obtained shows a strong dependence of the exchange coupling on both the FeOFe bond angle and the FeO bond distance. This correlation holds for both the ferric wheels and the alkoxo‐bridged FeIII dinuclear complexes reported in the literature. Ferric wheels: A theoretical study has been carried out to obtain the exchange coupling constants of eight ferric wheels. The graphic shows the magnetostructural correlation for such complexes, with the FeOFe angle and the FeO bond distance, in comparison with the results for dinuclear alkoxo‐bridged FeIII complexes.