Biochemistry 4th Edition by Reginald Garrett, Charles Grisham

Exercise 1

P700 has the most negative standard reduction potential found in Nature
In Photosystem I, P700 in its ground state has an E o' = +0.4 V. Excitation of P700 by a photon of 700-nm light alters the E o' of P700* to -0.6 V. What is the efficiency of energy capture in this light reaction of P700