Evidence for long-range electron transfer in a diffusion-influenced bimolecular reaction from fluorescence decay measurements

✍ Scribed by A.D. Scully; T. Takeda; M. Okamoto; S. Hirayama

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 752 KB
• Volume: 228
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(94)00918-x

✦ Synopsis

The effect of pressure-induced changes in solvent viscosity on the kinetics of intermolecular electron transfer between eleo tronically excited 9,lO-diphenylanthracene and maleic anhydride in acetonitrile was investigated using time-resolved fluorescence measurements. The nonexponential fluorescence decay curves were analyzed using the long-time approximation to the Smoluchowski-Collins-Kimball equation for diffusion. The value obtained for the reaction distance, R, is significantly larger than the sum of the molecular radii of these reactants, lending support to the proposal that the optimum rate constant for electron transfer may occur at a distance significantly longer than the contact distance. T'he value for the intrinsic reaction rate constant, k,,, calculated in this work is an order of magnitude smaller than that reported previously by others.