Optical Spectroscopy of Triplets

Triplet species absorb light to give higher excited triplets and thus have characteristic ultraviolet and visible spectra. This phenomenon was discovered for phosphorescent fluorescein in 1941 by Lewis and 

7 Triplet-triplet absorption spectra are the most common tool used for monitoring transients produced in flash spectroscopic experiments. The flash spectroscopic technique is used not only to detect triplets, but also to follow the kinetics of their decay, whether by physical processes or by chemical reaction. 

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AR Brown, K Pichler, NC Greenham, DDC Bradley, RH Friend, and AB Holmes, Optical spectroscopy of triplet excitons and charged excitations in poly(p-phenylenevinylene) light-emitting diodes, Chem. Phys. Lett., 210 61-66, 1993. 

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