Two-step sequential light-induced electron transfer in a simple trichromophoric donor-donor-acceptor system

The photophysical behavior of several porphyrin compounds were studied to determine the sequential charge transfer processes of molecules with simple organic building blocks. Excitation at 308 nm produced an acceptor moiety with a characteristic charge-transfer emission instead of fluorescence. The porphyrin compounds exhibited variations in their fluorescence with different quantum yield values and decay times. Estimations of the energetics of charge transfer are presented.