Photoinduced electron transfer of fullerenes such as C 60 and C 70 in the presence of aromatic aldehyde hydrazones (AAH's) has been studied by the nanosecond laser photolysis which measures the transient absorption spectra in the visible and near-IR regions. Electron-transfer takes place from AAH's to the triplet states of fullerenes; the rates and efficiencies of electron transfer are strongly affected by the electron-donor ability of AAH's as evaluated by their oxidation potentials. The absorption bands of the radical cations of AAH's appeared in the near-IR reagion, indicating that the radical-cation center (hole) delocalizes in the entire region of each AAH. On addition of a viologen dication to C 60/C 70-AAH, the electron of the anion radical of fullerenes moves to viologen dication yielding the viologen radical cation. In the systems of octaethyl porphyrinatozinc (ZnOEP)-C 60/C 70-AAH, the hole shift was observed from the radical cation of ZnOEP, which was produced by photoinduced electron transfer from the triplet state of ZnOEP to C 60/C 70, to AAH.
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