Organometallic Polymers and Synthetic Photosynthesis Systems

A large number of chlorophyll antennas are used to harvest the solar energy, which in turn are used to excite the special pair P700. The P70o donor will in turn transfer an electron to a primary acceptor (A0, phyophytin) and in less than 100 ps to a secondary acceptor (Ai, a phylloquinone). The electron received by Ai is in turn transferred to an iron-sulfur cluster and then to the terminal iron-sulfur acceptor.41 

FIGURE 22. Types of metal-containing polymers. (Modified from Ref. 61a.) 

Harvey et al. studied the photophysical properties of macromolecules built on M-P and M-CN (isocyanide) bonds, including the metal in the backbone. (This topic is reviewed in Chapter 2. The presence of the metal atom associated with the porphyrin moiety is examined here. 

The approach for this system is the mimicry of the highly efficient photosynthesis process in biological systems, by which an antenna device collects the light energy before a series of exciton, energy, and electron transfers, which lead to the synthesis of the plant s fuel.70-73 

Porphyrins are an interesting class of compounds used for the study of energy- and electron-transfer functions of the natural photosynthetic machinery. The interest in porphyrins is motivated in part by their photocatalytic activity and electronic properties.74 Porphyrins are also structurally related to chlorophyll. 

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