The change of colour which occurs when chemicals are put under stress in the solid state by mechanical grinding, crushing and milling; by friction and rubbing; or in the solid or solution state by high pressure or
sonication
image:Sonicator.jpg, A sonicator at the Weizmann Institute of Science during sonicationSonication is the act of applying sound energy to agitate particles in a sample, for various purposes such as the extraction of multiple compounds from plants, ...
is covered by the generic term mechanochromism. Specifically colour change under pressure is known as
piezochromism and under grinding or attrition
tribochromism.
See also
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Chromism
In chemistry, chromism is a process that induces a change, often reversible, in the colors of compounds. In most cases, chromism is based on a change in the electron states of molecules, especially the π- or d-electron state, so this phenomenon i ...
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Photoelasticity
In materials science, photoelasticity describes changes in the optical properties of a material under mechanical deformation. It is a property of all dielectric media and is often used to experimentally determine the stress distribution in a ...
(for the physical process)
References
1. Bamfield, Peter and Hutchings, Michael G, Chromic Phenomena: the technological applications of colour chemistry, Royal Society of Chemistry, Cambridge UK, pages 104–5, 2010. .
Chromism
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