Chemistry in Pictures: Beaming with pride | Chemical & Engineering News

Issue Date: January 30, 2018 | Web Date: January 31, 2018

Chemistry in Pictures: Beaming with pride

Department: Science & Technology
Keywords: Chemistry in Pictures, iodine, fluorescence, sublimation, vapor
Credit: Andres Tretiakov
A photo of a flask in a dark room with a green laser pointer shining on it, the beam of which appears orangey red inside the flask.
Credit: Andres Tretiakov

Andres Tretiakov, a laboratory technician at a high school in London, had read that iodine vapor fluoresces when excited by a helium-neon laser. So he decided to give it a go. After heating a few solid iodine crystals so they’d sublime—turn from solid to gas—he shined his green laser pointer through the flask. “To my surprise, I saw that it had worked,” Tretiakov says. The iodine vapor glowed orangey yellow when excited by the laser light, which had a wavelength of 532 nm.

Submitted by Andres Tretiakov

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