| Abstract
| - Picosecond absorption spectroscopy is employed in the study of the reaction dynamics for thecontact ion pairs produced upon the photolysis of a series of substituted diphenylmethyl acetates in thesolvents acetonitrile, dimethyl sulfoxide, and 2,2,2-trifluoroethanol. From the temperature dependence ofthe rate constants, the activation parameters associated with covalent bond formation and diffusionalseparation to the solvent-separated ion pair are obtained. The activation parameters for bond formationare examined within the context of the Hynes theory for solvent dynamical effects on the passage throughthe transition state; deviations from the transition-state theory are found to be large. Factors that controlnucleophilicity are discussed. Finally the validity of applying the Marcus equation to the SN1 reactionmechanism is addressed.
|
