In connection with the Agmon-Hopfield relaxational model, peculiaritie
s in the time and temperature dependence of the rate of CO-heme rebind
ing after laser-flash-induced dissociation are treated. Two cases are
compared - well-type and hump-type relaxation. They correspond to expe
ctations of different results in experiments and should provide furthe
r verification of the relaxational model of the mechanism and kinetics
of MbCO rebinding.