KINETIC-THEORY OF BIMOLECULAR REACTIONS IN LIQUID - 1 - STEADY-STATE FLUORESCENCE QUENCHING KINETICS

A microscopic kinetic theory for steady-state fluorescence quenching r eaction in liquid is formulated. Based on a linear reaction-liouville equation for the distribution function in phase space, we derived a me mory equation for the relaxation of singlet density function of reacta nts by use of Mori's projection operator technique. The expression of the memory kernel is analyzed by the fully renormalized kinetic theory developed by Mazenko. The memory kernel includes the many-body inform ation via a hierarchical structure of a propagator in that. This hiera rchy is truncated by a disconnected approximation for the propagator g overning the dynamics of an orthogonalized doublet field creating thei r initial correlation via a bimolecular interaction. This approximatio n is different from the dynamic superposition approximation for reduce d distribution functions made in usual hierarchical approaches. As a r esult, the detailed description of reactant dynamics becomes available and the memory kernel consists of a geometric series describing the r epeated ring collision (reaction) events. We obtain a self-consistent algebraic equation at the diffusion level, which is easily solved by a few iteration, for the response of concentration of reactants to a co nstant external perturbation. The effects of intensity of external con stant perturbation are explicitly considered. The present theory yield s the same result with that of the mean-field diffusion theory althoug h the approximations and the assumptions are quite different from each other. (C) 1998 American Institute of Physics.