Chemistry of ice surfaces. Elementary reaction steps on ice studied by reactive ion scattering.

This Account describes a recent study of reactions on ice surfaces with the emphasis on the mechanistic features of elementary reactions steps. Cs(+) reactive ion scattering (Cs(+) RIS) and low-energy sputtering (LES) techniques monitor the reactions by detecting the molecules and ions on the ice surface. The types of reactions include molecule diffusion and migration, proton transfer, and some simple reactions on frozen water and alcohol surfaces. Ice surface reactions exhibit unique behaviors due to a kinetic constraint, resulting in the isolation of reaction intermediates, preferential stabilization of charged species, and diversity of reaction products.