Solubility determination and crystallization thermodynamics of an intermediate in different organic solvents

Selectively Altering the Reactivity of Transient Organic Radical Ions via Their Solvation Environment

Photoexcitation of the charge transfer band of electron donor-acceptor complexes composed of toluene and 1,2,4,5-tetracyanobenzene yields organic radical ion pairs whose ultrafast reactive dynamics are determined by equilibrium solvent properties. A comparative study of ultrafast reaction rates in a series of alkane alcohols identified their dependence on the local polarizability and hydrogen bond donating/accepting character of the solvent. Because of the rapid and efficient equilibration of these radical ion pairs into solvent-separated species, simple modifications to bulk conditions can be used as a means to selectively alter their decay rates. Selectively altering distinct stages in this photochemical cycle via cosolutes or additives is a valuable step toward understanding and controlling the reactivity of organic radical ions in complex environments.