Marcus kinetic theory maximum rate

It can be seen that obtaining maximum efficiency from a cell relies on the solubihty of the dye (A), an extremely rapid rate constant for the A, B couple, and relatively slow kinetics for the electron-transfer reaction of B and Y. It is inconceivable that electron-transfer reactions obeying the above conditions while at the same time satisfying the Marcus theory could occur [16, 21-23]. 

---