Conference paper

Publication year: 2009

Pages: 28-34

Journal: Journal of Molecular Spectroscopy

Volume number: 256

Issue number: 1

ISSN: 0022-2852

DOI Link: https://doi.org/10.1016/j.jms.2009.01.010

Conference: 20th International Conference on High Resolution Molecular Spectroscopy

Publisher: Elsevier

Abstract: 
Using high-resolution Fourier transform spectra of mono deuterated formaldehyde (HDCO) recorded in the 5.8-mu m spectral range at Giessen (Germany), we carried out an extensive analysis of the strong nu(3) fundamental band (carbonyl stretching mode) at 1724.2676 cm(-1), starting from results of a previous analysis [J.W.C. Johns, A.R.W. McKellar, J. Mol. Spectrosc. 64 (1977) 327-339]. For this hybrid band (with both A- and B-type transitions) the analysis was pursued up to high rotational quantum numbers. In this way, it was possible to evidence a resonance which perturbs the nu(3) lines for high K-a values which is due to the existence of the 2 nu(5) and nu(5) + nu(6) dark bands in the same spectral region. In addition a local resonance is perturbing the 3(1) levels in K'(a) = 8 which is due to a crossing with the 4(1) energy levels in K-a = 11. The model used to calculate the energy levels accounts for the observed A- type, B- type C-type Coriolis (and/or) Fermi resonances which couple the 3(1) and the 5(1)6(1), 5(2), and 4(1) energy levels. However the 4(1) state is also involved in strong vibration-rotation interactions coupling the {5(1),6(1),4(1)} system of resonation states of HIDCO [A. Perrin, J.M. Flaud, L. Margules, J. Demaison, H. Mader, S. Wormke, J. Mol. Spectrosc. 216 (2002) 214-224]. Therefore the final energy levels calculation was performed for the {5(1),6(1),4(1),3(1),5(2),5(1)6(1)} resonating states and in this way it was possible to reproduce the observed line positions, within their experimental uncertainties. The present work also led to the determination of the intensity ratio of the B- to A-type components of the nu(3) band I-A/I-B similar to 24 band from spectral fittings performed in several parts of the observed spectrum. Finally, using the 5.8 mu m band intensity available in the literature we generated, for the first time, a list of line parameters (positions and intensities) for the 5.8 mu m region of HDCO. v 2009 Elsevier Inc. All rights reserved.

Harvard Citation style: Gomez, L., Perrin, A. and Mellau, G. (2009) New Analysis of the ν3 fundamental band of HDCO: Positions and intensities, Journal of Molecular Spectroscopy, 256(1), pp. 28-34. https://doi.org/10.1016/j.jms.2009.01.010

APA Citation style: Gomez, L., Perrin, A., & Mellau, G. (2009). New Analysis of the ν3 fundamental band of HDCO: Positions and intensities. Journal of Molecular Spectroscopy. 256(1), 28-34. https://doi.org/10.1016/j.jms.2009.01.010