Kinetics of Ionic Processes in the Radiolysis of Liquids. II. Proton Transfer from Cyclohexane Ions to Ethanol

Abstract

The extent to which positive ions produced by the radiolysis of cyclohexane undergo proton transfer to a dissolved scavenger before geminate recombination has been studied by an isotopic method. Ethanol‐d (C₂H₅OD) has been used, and the yield of HD is related to the yield of scavengable ions. The yield is strongly dependent on ethanol concentration over most of the range but at high concentration (>1M) a limiting value is reached corresponding to an estimated total yield of 2.6 ion/100 eV. The dependence of the yield on scavenger concentration suggests that the distribution of recombination times for ion pairs lies in the range between 10⁻⁷ and 3×10⁻¹¹ sec corresponding to initial separation distances between 280 and 19 Å, respectively. A median separation distance of 50 Å is indicated. The results are consistent with the earlier supposition that the electron is trapped as a negative entity with molecular dimensions. Some implications of this model are examined.