Free Energy Dependence of the Intrinsic Rate of Electron Transfer in Diffusional Quenching of trans-Stilbene S1 by Electron-Deficient Olefins

Article abstract of DOI:10.1021/j100162a033

The quenching of the first excited singlet states of trans-stilbene and 4,4'-dimethyl-trans-stilbene by acrylonitrile, fumaronitrile, and tetracyanoethylene has been examined by picosecond laser spectroscopy.The intrinsic rate constant of electron transfer is separated from the diffusion rate constant by applying the Collins and Kimball formalism for time-dependent rate constants.The intrinsic rates of electron transfer are correlated with the free energy changes for electron transfer, and it is found that the correlation does not follow the predictions of Marcus' adiabatic electron-transfer theory.