Rate constants of primary reversible reactions of electron transfer do not depend on temperature. Numerical experiment

The process of irreversible photochemical charge separation in photosynthetic bacterial reaction centers is proposed to be characterized by the effective rate constant. A formula to compute this effective rate constant is derived. Similar rate constant was previously considered by R.A. Marcus (Marcus R.A. 1956. J. Chem. Phys. 24, 966–978) in order to describe nonphotochemical intermolecular electron transfer. The effective rate constant of the irreversible charge separation in photosynthetic bacterial reaction centers is shown to depend on the temperature. In contrast, rate constants of the forward electron transfer from the excited singlet primary donor to the bacteriochlorophyll and from its ion-radical to the bacteriopheophytin acceptor do not depend on temperature.