Luminescence

Angelo Albini[1]

Professor of Organic Chemistry at the University of Pavia, Italy

Luminescence, emission of light, usually defined as restricted to cold body emission, not caused by heath (that is rather called incandescence), upon occurring of a chemical or physical phenomenon. This term was first used by Q. L. Bum in 1888 [1], when studying systematically the emission(s) of (mainly organic) materials, and defined as follows "I would like to propose for this second type of exploiting light, for which we have not yet a name, propose the name of luminescence, and to tag the bodies that give light in such a way luminescent. Various types of luminescence are distinguished according to the mechanism involved [2-4], viz.

1. Chemical Excitation

• Chemoluminescence - luminescence caused by the occurring of a chemical reaction [5-8],
• Bioluminescence - luminescence caused by the occurring of a biochemical reaction in the cells [8],
• Electrochemicalluminescence - luminescence caused by the occurring of an electrochemical reaction [9-10].

2. Physical Excitation

• Lyoluminecence - luminescence occurring upon dissolving a solid in a liquid [11],
• Candoluminecence - luminescence occurring upon heating, but different from incandescence (thus, the emission differs from the blackbody emission at that temperature) [10, 12],
• Crystallochemiluminescence - luminescence occurring upon crystallization of a compound [13],
• Mechanoluminescence - (or essentially with the same meaning, triboluminescence or fractonochemiluminescence), luminescence occurring when exerting a mechanical action (scratching, rubbing, crushing) on a solid material [14],
• Piezoluminescence - luminescence occurring upon exerting a pressure on a solid material [15],
• Sonoluminescence - luminescence occurring when bubbles are caused to implode in a liquid, through the action of a sound [24],
• Photoluminescence, emission of light upon absorption of light of a different (and generally shorter) wavelength, distinguished in fluorescence, phosphorescence and Raman emission, see the corresponding lemma),
• Thermoluminescence - re-emission of light previously absorbed, different from black-body emission [21],
• Cryolumiescence - luminescence occurring upon cooling a material [23],
• Radioluminscence - luminescence occurring upon hitting a material by ionizing (short wavelength) radiation [22],
• Sonoluminescence - luminescence caused by the vibrations of sound [24].

References