Reactions of Solvated Electrons Initiated by Sodium Atom Ionization at the Vacuum-Liquid Interface

Solvated electrons are powerful reagents in the liquid phase that break chemical bonds and create new reactive species, including hydrogen atoms. Electrons and hydrogen atoms born near the surface, however, behave differently than those created within the liquid. We explore this behavior by exposing liquid glycerol to a beam of sodium atoms. The Na atoms ionize in the surface region, generating electrons that react with deuterated glycerol, C$_{3}$D$_{5}$(OD)$_{3}$, to produce D atoms, D$_{2}$, D$_{2}$O, and glycerol fragments. Surprisingly, 40{\%} of the D atoms desorb into vacuum before attacking C-D bonds to produce D$_{2}$. These D atoms must traverse the interfacial region before desorbing, demonstrating that Na ionization prepares reactive species that reside momentarily at the surface and often escape before reacting with the solvent.