| Abstract
| - Previous computer simulations and surface-selective spectroscopic experiments indicated non-monotonicconcentration depth profiles for soft inorganic ions (such as iodide) at the air/water interface while this surfaceeffect was strongly quenched in methanol. Here, we investigate by means of neutral impact collision ionscattering spectroscopy and molecular dynamics simulations the surface propensity of anions of alkali halideiodide salts in formamide. By combination of experiments and calculations, we extract both the ionconcentration depth profiles at the interface and the local solvent topography around the ions in or near thetopmost layer of the liquid. We show that formamide, as a nonaqueous polar solvent containing no hydrophobicgroups, exhibits an enhanced surface coverage of soft inorganic ions like iodide and that the ions are locatedin the outermost layer in valleylike structures. The non-monotonic interfacial concentration profile and surfacepropensity of iodide in formamide is quantified and compared to that in water.
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