chemiluminescence

n. production of light at low temperatures (in chemical reactions)

Chemiluminescence (sometimes "chemoluminescence") is the emission of light (luminescence) without emission of heat as the result of a chemical reaction. Given reactants A and B, with an excited intermediate ◊, we have:[A] + [B] → [◊] → [Products] + lightFor example, if [A] is luminol and [B] is hydrogen peroxide in the presence of a suitable catalyst we have:luminol + H2O2 → 3-APA[◊] → 3-APA + lightwhere:where 3-APA is 3-aminophthalate3-APA[◊] is the excited state fluorescing as it decays to a lower energy level.
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Chemiluminescence /chemi·lu·mi·nes·cence/ luminescence produced by direct transformation of chemical energy into light energy. [more]Chemiluminescence - Community and Resources

Noun
1. luminescence resulting from a chemical reaction as the oxidation of luciferin in fireflies
(hypernym) luminescence

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A chemical reaction that releases energy as electromagnetic radiation.