In this study the existence of the C-60 cation produced by photochemically
induced electron transfer in the presence of different sensitising molecule
s is proved for the first time by using ESR spectroscopy. It is demonstrate
d for triphenylpyryliumtetrafluoroborate (TPP) by this spectroscopic method
that the electron transfer from C-60 to TPP occurs without, an application
of a cosensitiser. Furthermore it is shown that the addition of alcohols c
auses a new radical in the system C-60/TPP. The stationary concentration of
the C-60 cation diminishes even in the presence of a cosensitiser to such
a low concentration that it is not detectable by ESR spectrosopy. The spect
roscopic study of the sensitiser/C-60 system is also extended to the reacti
on products.