Long-time tails in the kinetics of reversible bimolecular reactions

A new approach is developed to study the relaxation of concentrations to eq uilibrium in reversible bimolecular reactions. For A + B reversible arrow C . a general analytic expression is derived for the amplitude of the power l aw (t(-d/2)) asymptotics for arbitrary diffusion coefficients and concentra tions of the reactants. Our formalism is based on the analysis of the time correlation functions describing the equilibrium fluctuations of the concen trations. This powerful and simple procedure can be readily used to study o ther bimolecular reactions such as A + B reversible arrow C + D.