N2-Broadening Study in the n2 Band of methyl chloride

Résultats de recherche: Contribution à un événement scientifique (non publié)Poster

Résumé

Since the diminution of utilization of the CFC gases following the Montreal Protocol [1], methyl chloride has become one of the main sources of chlorine ions in the atmosphere [2], as the main sources are not only anthropomorphic activities, but also tropical forests [2] and biomass burnings [3]. In order to monitor with enough reliability the importance of methyl chloride in our atmosphere, one needs to determine his spectral parameters with high precision.

In the present work, we have measured N2-broadening coefficients in the ν2 band of methyl chloride between 1335 and 1370 cm-1. The measurements were performed with a high resolution tunable diode laser spectrometer [4], for 15 lines in the P and R branches, with J ranging from 4 to 20 and K varying from 2 to 7. For each line, four measurements of the collisional half-width were realized, with different nitrogen pressure, from around 15 to 55 mbar.

Collisional broadening coefficients were retrieved from the fit of Voigt [5], Rautian [6] and Galatry [7] line profiles on the experimental data. For the last two line-shapes, the Dicke narrowing effect [8] was taken into account. We analyzed the angular dependence and compared our results with previous studies in the ν1 [9] and ν3 [10] bands.

References

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W.T. Sturges, et al. Ozone-Depleting Substances (ODSs) and Related Chemicals, chapter 1 in
Scientific Assessment of Ozone Depletion: 2010, Global Ozone Research and Monitoring
Project–Report No. 52, 516 pp., World Meteorological Organization, Geneva, Switzerland,
2011.
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(2012)
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[7] L. Galatry, Phys. Rev. 122, 1218-1224 (1960)
[8] R.H. Dicke, Phys. Rev. 89, 472-473 (1953)
[9] C. Bray, D. Jacquemart, J. Buldyreva, N. Lacome, A. Perrin, J. Quant. Spectrosc. Radiat.
Transfer 113, 1102–1112 (2012)
[10] G. Blanquet, J. Walrand and J.-P. Bouanich, J. Mol. Spectrosc. 160, 253-257 (1993)
langue originaleAnglais
Etat de la publicationPublié - sept. 2014
EvénementThe 23rd International Conference on High Resolution Molecular Spectroscopy - Bologne, Italie
Durée: 2 sept. 20146 sept. 2014

Une conférence

Une conférenceThe 23rd International Conference on High Resolution Molecular Spectroscopy
PaysItalie
La villeBologne
période2/09/146/09/14

    Empreinte digitale

Contient cette citation

Leonis, S., & Lepere, M. (2014). N2-Broadening Study in the n2 Band of methyl chloride. Poster présenté � The 23rd International Conference on High Resolution Molecular Spectroscopy, Bologne, Italie.