Increased Propensity of I-aq(-) for the Water Surface in Non-neutral Solutions: Implications for the Interfacial Behavior of H3Oaq+ and OHaq-
By a combination of surface-sensitive photoelectron spectroscopy and molecular dynamics simulations, we characterize the surface propensity of the iodide anion in aqueous solutions at acidic, neutral, and basic conditions (pH = 1, 6.8 and 13). In both experiments and simulations, an increased surface concentration of I- is found in non-neutral solutions. We interpret these findings in terms of I-