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Updated: Jun 15, 2026

Ultrafast Time-resolved Near-IR Stimulated Raman Measurements of Functional π-conjugate Systems
Published on: February 10, 2020
Infrared absorption bands of alpha and beta -pinenes in the 8-14-microm atmospheric window region
Abstract:
There are bands in the 8 -14-microm atmospheric window region of the gas phase IR spectra of alpha- and beta-pinenes that are intense enough to allow theoretically the naturally occurring terpenes to be determined in the 100- ppbv level at 1-km path lengths. Because of the broadness of the bands, however, and the relatively intense atmospheric background at their frequencies of 786.5 cm(-1) and 880 cm(-1), respectively, practical concentration limits for the use of the bands are probably not better than about 1-10 ppmv. Both type C bands have 4-cm(-1)Q branches which fall at frequencies which are essentially free of any major atmospheric fine structure bands.
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