Optimisation of photoinduced electron transfer in photoconversion

As this chapter should have demonstrated, a detailed understanding of the mechanism of ET reactions has now been achieved by the efforts of many theoreticians and experimentalists, and we shall conclude it by reflecting on the lessons for photoconversion devices based on photoinduced electron transfer reactions. 

The powerful control exerted by the exponential dependence of ET rates on mnst 

Natiual photosynthesis, as we have already noted, seems to observe these tenets. The A value of reaction centre protein is 0.5 eV, which is in the ballpark of the -AG° values for the primary light-induced charge separation across a membrane, but much smaller than -AG° values for the highly exergonic unwanted back ET step. Also the reaction centre cofactors are so positioned as to provide molectrlar ET stepping stones for the 

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