Free Radicals Generated by Radiolysis of Aqueous Solutions.

The free radicals produced in the radiolysis of aqueous solutions span the range of redox potentials from -2.9 to +2.65 volts. The identity and nature of these radicals were discussed. Most of the discussion was results obtained with low LET radiation sources (/sup 60/Co gamma radiation or electron accelerators). Water radiolysis provides the synthesis of many radicals and radical ions in aqueous solution. The primary radicals, e/sub aq//sup -/ H, OH, are well characterized. The radical population can be made to be 90% pure OH (or O/sup -/) if N/sub 2/O solutions are irradiated, the remaining 10% being H atoms. 55% of the radicals can be converted to H atoms in acid solution or in neutral phosphate solutions(e/sub aq//sup -/ reacts with H/sub 2/PO/sub 4//sup -/ to produce H). The remaining 45% (OH radicals) are difficult to convert to H by reaction with H/sub 2/, due to the slow rate of the reaction. About 100 atmospheres of H/sub 2/ are required to do the conversion in less than 10/sup -6/ sec. 3 figures, 3 tables. (DP)