Photoinduced intramolecular electron-transfer reactions in carbazole (Cz)-fullerene (C
60) (Cz(8)C
60) and phenothiazine (Ph)-C
60 (Ph(
n)C
60 (
n=8, 10, 12)) linked compounds have been investigated in benzene and benzonitrile by fluorescence, transient absorption, and time-resolved electron paramagnetic resonance measurements, and by magnetic field effects on the decay rate constants of the photogenerated biradicals. In benzonitrile, photoinduced intramolecular electron transfer from Cz to the singlet excited state of C
60 (
1C
60 *) occurred in Cz(8)C
60, but not to the triplet excited state (
3C
60 *), while the intramolecular electron-transfer to both
1C
60 * and
3C
60 * occurred in Ph(
n)C
60 (
n=8, 10, 12). In benzene, on the other hand, no electron transfer to both
1C
60 * and
3C
60 * took place in all linked compounds. These results were interpreted in terms of the different Gibbs free energy changes in the two solvents.
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