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 Fe(III) dinuclear complexes reported in the literature.
Ruiz
Eliseo
E
Departament de Química Inorgànica and Centre Especial de Recerca en Química Teòrica Universitat de Barcelona, Diagonal 647, 08028, Spain. eliseo.ruiz@qi.ub.es
Alvarez
Santiago
S