Segregation of inorganic ions at surfaces of polar nonaqueous liquids.

We present a short review of recent computational and experimental studies on surfaces of solutions of inorganic salts in polar nonaqueous solvents. These investigations complement our knowledge of aqueous interfaces and show that liquids such as formamide, liquid ammonia, and ethylene glycol can also surface-segregate large polarizable anions like iodide, albeit less efficiently than water. For liquids whose surfaces are covered with hydrophobic groups (e.g. methanol), the surface-ion effect all but disappears. Based on the present data a general picture of inorganic-ion solvation at the solution-vapor interface of polar liquids is outlined.