(often a combination of gallium, arsenic and phosphorous or gallium and nitrogen)
containing an n
region (where electrons are more numerous than positive charges) separated from a
region (where positive charges are more numerous than negative charges). Upon application
of a voltage, charges move and emission of ultraviolet
radiation is produced each time a charge recombination
takes place. Although a LED
emits incoherent monochromatic light, normally a very narrow frequency
range is obtained.
This effect is a form of electroluminescence.
The colour depends on the semi-conducting material used, and can be ultraviolet, visible or infrared.
Organic light-emitting devices (OLEDs) contain diodes made of small molecules or made of polymeric materials. The latter are sometimes called PLEDs.
PAC, 2007, 79, 293
(Glossary of terms used in photochemistry, 3rd edition (IUPAC Recommendations 2006))
on page 364
IUPAC. Compendium of Chemical Terminology, 2nd ed. (the "Gold Book"). Compiled by
A. D. McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford (1997).
XML on-line corrected version: http://goldbook.iupac.org (2006-) created by M. Nic,
J. Jirat, B. Kosata; updates compiled by A. Jenkins. ISBN 0-9678550-9-8. https://doi.org/10.1351/goldbook