Primary processes of photosynthesis and their modeling

Photosynthesis is one of the most fascinating fields of current interdisciplinary research. It seems miraculous that Nature, in the process of evolution, has managed to bring about a 100 % quantum yield in charge separation occurring in the primary processes within the photosynthetic reaction centers. In fact, wasteful deactivation of the photoexcited electronic states into the ground state should be favored and thus prevent charge separation. Biomimetic model compounds have been synthesized, essentially from porphyrins and quinones, resembling the redox-active cofactors, Nature has developed. The underlying philosophy of this approach is to design and prepare suitable organic molecules allowing the specific properties of the complex electron transfer reactions to be tuned appropriately. Special emphasis is given the thorough comparison of structures and functions of native and artificial systems. The prominent electron transfer characteristics are discussed in particular by using time-resolved picosecond fluorescence and time-resolved EPR techniques.