Photoinduced electron transfer (PET) processes along redox cascades are of fundamental relevance in biology (e.g., photosynthesis) and in artificial devices such as dye sensitized (in)organic solar cells (DSSC) or solar cells based on semiconducting organic polymers.

Fully artificial redox cascades are synthesized in order to study directed photoinduced electron transfer along a redox gradient which results in a long-lived charge separated state.

These chromophores consist of an acridine acceptor and up to three triarylamine donor subunits with decreasing redox potential. The electronic coupling in between the redox subunits is tuned by sterical as well as electronic effects to investigate their influence on the kinetics of various deactivation pathways. The rates for population and depopulation of the involved excited states are determined by stationary and time-resolved fluorescence and absorption spectroscopy, respectively.