Ultrafast Chemistry of Water Radical Cation, H2O•+, in Aqueous Solutions

Oxidation reactions by radicals constitute a very important class of chemical reactions in solution. Radiation Chemistry methods allow producing, in a controlled way, very reactive oxidizing radicals, such as OH center dot, CO3 center dot, NO3 center dot, SO4 center dot, and N-3(center dot). Although the radical cation of water, H2O center dot+, with a very short lifetime (shorter than 1 ps) is the precursor of these radicals in aqueous solutions, its chemistry is usually known to be limited to the reaction of proton transfer by forming OH center dot radical. Herein, we stress situations where H2O center dot+ undergoes electron transfer reaction in competition with proton transfer.