singlet oxygen


sin·glet ox·y·gen

an excited or higher-energy form of oxygen characterized by the spin of a pair of electrons in opposite directions, whereas electron spin is unidirectional in normal molecular oxygen Because of its great reactivity, singlet oxygen is a probable intermediate in most photooxidation reactions. Although it exists for no more than 0.1 second, it may react with atmospheric pollutants to foster smog formation and may have harmful biologic effects.

singlet oxygen

A highly active form of oxygen produced during reactions of hydrogen peroxide with superoxide and hypochlorite ions. It is believed that this free radical is bactericidal. See also: oxygen