Advances in Electron Transfer Chemistry, Volume 4 presents the reaction mechanisms involving the movement of single electrons. This book discusses the electron transfer reactions in organic, biochemical, organometallic, and excited state systems. Organized into four chapters, this volume begins with an overview of the photochemical behavior of two classes of sulfonium salt derivatives. This text then examines the parameters that control the efficiencies for radical ion pair formation. Other chapters consider the progress in the development of parameters that control the dynamics and reaction pathways for radical ion pairs produced by the diffusional quenching of photoexcited molecules. This book discusses as well the criteria for distinguishing concerted from stepwise mechanisms in electrochemical and homogeneous reductive cleavage reactions in polar solvents. The final chapter deals with excited-state chemical transformation, particularly on photoinduced SET reactions in which amines and related substances serve as electron donors. This book is a valuable resource for scientists and electrochemists.