Chemiluminescence

Chemiluminescence (also chemoluminescence) is the emission of light (luminescence) as the result of a chemical reaction. There may also be limited emission of heat. Given reactants A and B, with an excited intermediate ◊,

${\displaystyle {\ce {[A]{}+[B]->{}[\lozenge ]{}->{}[products]{}+light}}}$

For example, if [A] is luminol and [B] is hydrogen peroxide in the presence of a suitable catalyst we have:

${\displaystyle {\ce {{\underset {luminol}{C8H7N3O2}}+{\underset {hydrogen\ peroxide}{H2O2}}->3-APA[\lozenge ]->{3-APA}+light}}}$

where:

• 3-APA is 3-aminophthalate
• 3-APA[◊] is the vibronic excited state fluorescing as it decays to a lower energy level.