Explanation of the Colour Change in Alexandrites.
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ABSTRACT:
SUBMITTER: Xie F
PROVIDER: S-EPMC7145866 | biostudies-literature | 2020 Apr
REPOSITORIES: biostudies-literature
Publications
Explanation of the Colour Change in Alexandrites.
Xie Fei F Cao Yu Y Ranchon Cindy C Hart Alan A Hansen Robin R Post Jeffrey E JE Whitney Coralyn W CW Dawson-Tarr Emma E Drew Alan J AJ Dunstan David J DJ
Scientific reports 20200409 1
Alexandrites are remarkable and rare gemstones. They display an extraordinary colour change according to the ambient lighting, from emerald green in daylight to ruby red in incandescent light from tungsten lamps or candles. While this colour change has been correctly attributed to chromium impurities and their absorption band in the yellow region of the visible light spectrum, no adequate explanation of the mechanism has been given. Here, the alexandrite effect is fully explained by considering ...[more]
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