Proton Transfer between Organic Molecules Caused by Light

PROTON exchanges between acidic and basic organic compounds in solutions take place spontaneously according to the relative proton `affinities' of the partners. The possibility of a proton transfer against the thermodynamic potential under the action of light seems not to have been demonstrated by a clear-cut experiment. In an investigation of photochemical reactions of organic compounds at low temperatures, we were able to show such an effect.