ESR-SPECTRA OF GAMMA-IRRADIATED SAMPLES OF IRON(III) BINUCLEAR COMPLEXES

gamma-Irradiation of mu-oxo-bridged binuclear iron complexes Fe(2)(III )OL(n) in a glycerol or dimethylformamide matrix at 77 K affords unsta ble mixed-valence (FeFIII)-F-II forms resulting from the transfer ofa mobile electron generated by the ionizing radiation. These nonequilibr ium forms retain the ligand environment of the original complexes, and their ESR spectra at 77-200 K are characterized by an asymmetric sign al with an axially anisotropic g-factor, which is in agreement with th e spectra of the (FeFeIII)-Fe-II forms obtained by chemical reduction.