A page from the "Causes of Color" exhibit...



Causes of Color is one of several exhibits in the WebExhibits online museum, all of which promote discovery through multidisciplinary approaches that support all learning styles. WebExhibits is a public service of the Institute for Dynamic Educational Advancement (IDEA).

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Curated by Michael Douma. Content by Taryn Biggs and Susan McPhail. Based on the work of Kurt Nassau. Contributers include Sang Yoon Lee, Juraj Lipscher, and Margaret Stenerson. Edited by Sally Smith. For more information, see the credits page and the detailed references.


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Note about the selected "mechanisms": As with many forms of classification, when we impose an order on a set of facts there is more than one way to do so. Nassau in his classic book on the causes of color chooses fifteen principal mechanisms. These are grouped into five categories: simple excitations and vibrations, geometrical and physical optics, transitions involving energy bands, transitions between molecular orbitals, and transitions involving ligand fields. The first three are described by the concepts of physics, the fourth by those of chemistry and the fifth using both disciplines. Because the causes of color are so diverse, there are various ways to group them; in this WebExhibit we have chosen to group the causes to discuss where light is Made, Moved or Lost to create color.