Contact and Distant Luminescence Quenching in Solutions

Abstract

The limitations and advantages of modern encounter theories of remote transfer are discussed, as well as their application to particular transfer reactions assisted by encounter diffusion. Comparison is made with contact multiparticle theories, Brownian dynamic simulations, and the actual experimental data requiring a distant description of energy and/or electron transfer.

Unified Theory of the Exciplex Formation/Dissipation

“…The rate of the remote irreversible electron transfer is well approximated by either the exponent or the bell-shaped curve shifted a bit from the contact: 1,7 Here l is approximately the tunneling length, while ∆ is related to the reorganization energy of electron transfer in polar media and R > σ.…”

“…10 It was proved to obey the integral kinetic equation that was later on shown to be identical to that of IET 11 and works equally well for exciplex dissociation for either charged or neutral components. 6, 11 The corresponding IET equations for reaction 1.1 accounting not only for dissociation but also for the association, were proposed much later: 7,12,13 Here N* is the excited state population of electron donor, N E is that of the exciplex and c ) [A] is the concentration of the electron acceptors. The kernel of these equations in highly polar solvents (assuming an Onsager radius r c ) 0) has the following Laplace transformation:…”

Decay of Metastable State with Account of Agglomeration and Relaxation Processes

“…The first-order phase transition kinetics is actively investigated since the publication of the pioneer papers by Wilson [1][2][3] concerning the famous chamber which became the main tool in investigations of the microworld. The range of applications of the first-order phase transition kinetics inevitably grows since the phenomena concerning the selforganization [4,5] and aggregation [6] become the field of application of ideas lying in the base of the mentioned kinetics. The word "nucleation" has nothing in common with nuclear phenomena but comes from the evident fact that the embryos of a new phase are rather compact objects and can be treated as some nucleus of a new phase.…”

Analysis of transformations of the ultrafast electron transfer photoreaction mechanism in liquid solutions by the rate distribution approach

“…1 Various theoretical studies of these reactions involve MD and QC calculations [2][3][4] as well as uniform models. 5,6 However, a problem of the correct quantitative comparison of these data is very important. In particular, a well-known ambiguity of the recovery of the reaction mechanism from the reaction kinetics N(t ) can be misleading, when simple coincidence of the experimental and simulated data is considered as confirmation of the postulated mechanism.…”