Long-range perylene fluorescence quenching by electron acceptors

Diffusion-controlled fluorescence quenching for perylene by dinitrobenzene has been examined; Smoluchowski's equation does not apply. The reaction radius R in relatively viscous solvents (isopropanol and benzonitrile) exceed the contact radius by more than a factor two. R decreases as the mutual diffusion coefficient D increases. The in D dependence for R has been used to determine the electron-tunneling parameters. The Frank-Condon factors increase with the electron-acceptor strength. Electron-tunneling barrier heights from excited perylene to the oxidizing agent have been calculated. It is concluded that virtual solvent states are involved.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 24, No. 6, pp. 672–677, November–December, 1988.We are indebted to G. P. Gurinovich, Corresponding Member, Belorussian Academy of Sciences, for support in this work and for providing facilities for the measurements, and to Professor A. I. Burshtein for discussion.