Full temporal resolution of the two-step photoinduced energy-electron transfer in a fullerene-oligothiophene-fullerene triad using sub-10 fs pump-probe spectroscopy
Pa. Van Hal et al., Full temporal resolution of the two-step photoinduced energy-electron transfer in a fullerene-oligothiophene-fullerene triad using sub-10 fs pump-probe spectroscopy, CHEM P LETT, 345(1-2), 2001, pp. 33-38
The intramolecular photoinduced energy and electron transfer in a fullerene
-oligothiophene-fullerene triad with nine thiophene units (C-60-9T-C-60) ha
s been investigated with sub-10 fs pump-probe spectroscopy in solvents of d
ifferent polarity. Photoexcitation of the oligothiophene moiety results in
an ultrafast singlet-energy transfer reaction to create the fullerene singl
et-excited state with a time constant of 95 fs, irrespective of the polarit
y of the medium. In a polar solvent, the ultrafast singlet-energy transfer
is followed by intramolecular electron transfer from the oligothiophene to
the fullerene with a time constant of 10 ps, resulting in a charge-separate
d state (CSS) with a lifetime of 80 ps. (C) 2001 Elsevier Science B.V. All
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