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Observation of the C2H2-N2O van der Waals Complex in the Overtone Range Using CW-CRDS
Published
Author(s)
Walter J. Lafferty
Abstract
A slit nozzle supersonic expansion containing acetylene (0.246l/min) and nitrous oxide (0.355l/min) seeded into Ar (1.26l/min) is investigated using CW cavity ring down spectroscopy, in the 1.5 m range. The C2H2N2O van der Waals complex is observed around the 2CH acetylenic band. Despite strong perturbations, 117 b-type lines are assigned. Their combined fit with published microwave data leads to new upper state and improved lower state rotational constants. The Lorentzian width of the assigned line profiles sets the mean lifetime to 1.6 ns. The rotational temperature is estimated to be 15K from the comparison between observed and simulated spectra.
C-H Overtone Region, Perturbation, Rotational Constant, Van der Waals Complex
Citation
Lafferty, W.
(2009),
Observation of the C2H2-N2O van der Waals Complex in the Overtone Range Using CW-CRDS, Chemical Physics Letters, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=901007
(Accessed October 20, 2025)