Kinetic Isolation of Reaction Intermediates on Ice Surfaces. Precursor States of SO<sub>2</sub> Hydrolysis KimYoung-Kwang KimSun-Kyung KimJung-Hwan KangHeon 2009 We studied the interaction of SO<sub>2</sub> with ice films at temperatures above 80 K, with emphasis on the examination of the precursor states of SO<sub>2</sub> hydrolysis, or SO<sub>2</sub> surface complexes. Cs<sup>+</sup> reactive ion scattering (RIS) and low energy sputtering (LES) techniques were used to examine the surface reaction products, in conjunction with temperature-programmed desorption (TPD) to monitor the desorbing species. The study indicated that the reaction of SO<sub>2</sub> with the ice surface occurred through several distinct intermediate states, including a solvated SO<sub>2</sub> species, a DSO<sub>2</sub> species, and a strongly ionic molecular species, and these intermediates could be isolated on the ice surface due to kinetic trapping.