Light harvesting, excitation energy/electron transfer, and photoregulation in artificial photosynthetic systems

This chapter summarizes recent research from our laboratory on multichromophoric molecules that perform as components of artificial photosynthetic systems. The basic scientific principles underlying the design of these molecules were drawn from natural photosynthetic energy conversion, but thematerials used to prepare them are synthetic. The systems consist of chromophores and electron and energy donors and acceptors that have been chemically linked to form artificial reaction centers and antennas, and to mimic some aspects of photosynthetic regulation and photoprotection. These chromophores include porphyrins, fullerenes, carotenoid polyenes, antenna moieties, and photochromic materials. We begin with an introduction to artificial photosynthesis and a simple example. More complex systems including multichromophore arrays and systems that incorporate photoregulatory elements are then discussed. We have chosen examples based on a single organic framework-hexaphenylbenzene-as an organizing unit for the various chromophores, donors, and acceptors.