Hill reaction

The light-induced transport of electrons from water to nonphysiological electron acceptors, e.g. potassium ferricyanide, with the concomitant evolution of oxygen. The result is the reduction of the electron acceptor (Hill reagent) against the chemical gradient. Four moles of potassium ferricyanide are reduced for every mole of oxygen evolved. The reaction is named after Robin Hill, who discovered it in isolated chloroplasts in 1937.