Summary Principles of Photosynthetic Water Splitting

From the previous arguments, the WOC has five features that need to be emulated for rational synthetic catalyst design  

A multimeric transition metal complex (Mn4OsCa cluster) is employed to transiently store equivalents generated by fast electron photochemistry that are subsequently used to perform slow four-electron water-splitting chemistry. 

The substrate water molecules are prepared in a stepwise fashion for 0-0 bond formation by binding to the M OjCa cluster and by (partial) deprotonation. The concerted oxidation of the activated substrate occurs then either in two 2e steps or in one concerted 4e reaction step, thus avoiding high-energy intermediates. It is the matrix (protein) and the Ca2+/CF ions that allow for the coupling of proton- and electron-transfer reactions to occur. These features are 

4 Molecular Concepts of Water Splitting Nature s Approach 

The release of the products of the water-splitting reaction (O2 and H+) from the catalytic site is decoupled. 

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