UV-Light-Induced Hydrogen Transfer in Guanosine-Guanosine Aggregates

Aggregates of a lipophilic guanine (G) derivative have been studied in n-hexane by femtosecond-to-microsecond UV-visible broadband transient absorption, stationary infrared and UV-visible spectroscopy and by quantum chemical calculations. We report the first time-resolved spectroscopic detection of hydrogen transfer in GG aggregates, which leads to (GH). radicals by means of G+G charge transfer followed by proton transfer. These radicals show a characteristic electronic spectrum in the range 300550nm. The calculated superimposed spectrum of the species that result from NHN proton transfer agrees best with the experimental spectrum.