Editing Triboluminescence (section)

== Mechanism of action ==
There remain a few ambiguities about the effect. The current theory of triboluminescence—based upon crystallographic, spectroscopic, and other experimental evidence—is that upon fracture of asymmetrical materials, [[electric charge|charge]] is separated. When the charges recombine, the electrical discharge ionizes the surrounding air, causing a flash of light. Research further suggests that crystals that display triboluminescence often lack symmetry and are poor conductors.<ref name="Fontenot Bhat Hollerman Aggarwal 2012 pp. 1382–1386">{{cite journal | last1=Fontenot | first1=R. S. | last2=Bhat | first2=K. N. | last3=Hollerman | first3=W. A. | last4=Aggarwal | first4=M. D. | last5=Nguyen | first5=K. M. | title=Comparison of the triboluminescent yield and decay time for europium dibenzoylmethide triethylammonium synthesized using different solvents | journal=CrystEngComm | publisher=Royal Society of Chemistry (RSC) | volume=14 | issue=4 | year=2012 | issn=1466-8033 | doi=10.1039/c2ce06277a | pages=1382–1386}}</ref>  However, there are substances which break this rule, and which do not possess asymmetry, yet display triboluminescence, such as hexakis(antipyrine)terbium iodide.<ref>{{cite journal|author=W. Clegg, G. Bourhill and I. Sage|title=Hexakis(antipyrine-O)terbium(III) triiodide at 160 K: confirmation of a centrosymmetric structure for a brilliantly triboluminescent complex|journal=Acta Crystallographica Section E| date=April 2002 |volume=58|issue=4|doi=10.1107/S1600536802005093|doi-access=free|pages=m159–m161|bibcode=2002AcCrE..58M.159C }}</ref>  It is thought that these materials contain impurities, which make the substance locally asymmetric. Further information on some of the possible processes involved can be found in the page on the triboelectric effect.

The biological phenomenon of triboluminescence is thought to be controlled by [[Radical disproportionation|recombination]] of [[free radicals]] during mechanical activation.<ref>{{citation | journal= Bioluminescence and Chemiluminescence| pages= 239–244| first1= V.E. | last1= Orel | first2= S.B. | last2= Alekseyev | first3= Yu.A. | last3= Grinevich| year=1992 | title=Mechanoluminescence: an assay for lymphocyte analysis in neoplasis | doi=10.1002/bio.1170070403 | pmid= 1442175| volume=7| issue= 4}}</ref>