Photoinitiated electron transfer in multichromophoric species: Synthetic tetrads and pentads

Technical Report · Mon Mar 01 04:00:00 EST 1993

DOI:https://doi.org/10.2172/41331· OSTI ID:41331

This project involves the design, synthesis and study of molecules which mimic some of the important aspects of photosynthetic electron and energy transfer. This research project is leading to a better understanding of the energy conserving steps of photosynthesis via the study of synthetic model systems which abstract features of the natural photosynthetic apparatus. The knowledge gained from these studies will aid in the design of artificial photosynthetic reaction centers which employ the basic chemistry and physics of photosynthesis to help meet mankind`s energy needs. The approach to artificial photosynthesis employed in this project is to use synthetic pigments, electron donors, and electron acceptors similar to those found in biological reaction centers, but to replace the protein component with covalent bonds. These chemical linkages determine the electronic coupling between the various moieties by controlling separation, relative orientation, and overlap of electronic orbitals. The model systems are designed to mimic the following aspects of natural photosynthetic electron transfer: electron donation from a tetrapyrrole excited single state, electron transfer between tetrapyrroles, electron transfer from tetrapyrroles to quinones, and electron transfer between quinones with different redox properties. In addition, they mimic carotenoid antenna function in photosynthesis (singlet-singlet energy transfer from carotenoid polyenes to chlorophyll) and carotenoid photoprotection from singlet oxygen damage (triplet-triplet energy transfer from chlorophyll to carotenoids).

• Research Organization: Arizona State Univ., Tempe, AZ (United States). Dept. of Chemistry and Biochemistry
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: FG02-87ER13791
• OSTI ID: 41331
• Report Number(s): DOE/ER/13791--T2; ON: DE95009806
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
40 CHEMISTRY
CHEMICAL PREPARATION
ELECTRON SPIN RESONANCE
ELECTRON TRANSFER
EXPERIMENTAL DATA
PHOTOCHEMISTRY
PHOTOSYNTHETIC REACTION CENTERS
PORPHYRINS
PROGRESS REPORT
PYRROLES
QUINONES
SPECTROSCOPY