NEW ANALYSIS OF THE $\nu_{5}$ AND $2\nu_{g}$ BANDS OF $HNO_{3}$ BY HIGH RESOLUTION FOURIER-TRANSFORM INFRARED SPECTRA IN THE $11 \mu m$ REGION AND BY CM-TECHNIQUES: LINE POSITIONS AND LINE INTENSITIES
Loading...
Date
2003
Authors
Perrin, A.
Orphal, J.
Flaud, J.- M.
Klee, S.
Mellau, Georg C.
Mäder, H.
Walbrodt, D.
Winnewisser, M.
Journal Title
Journal ISSN
Volume Title
Publisher
Ohio State University
Abstract
Nitric acid $(HNO_{3})$ plays an important role in the Earth's atmosphere as a reservoir molecule of $NO_{x}$ species. This molecule has a strong infrared signature at $11 \mu m$ which is one of the most commonly used for the infrared retrieval of $HNO_{3}$ in the atmosphere since this spectral region coincides with an atmospheric window. It is therefore essential to have the best possible spectral parameters in this spectral region. The main goal of this work was to get better line positions and intensities for the $\nu_{5}$ and $2\nu_{g}$ cold bands located at 879.1088 and $896.4482 cm^{-1}$ respectively. This work was also motivated by theoretical considerations. Very strong resonances involve the $v=5^{1}$ and $v=9^{2}$ rotational levels. In addition the $\nu_{9}$ mode (OH torsion) is a ""large amplitude"" motion, and the torsional splittings are easily observed in the mm/submm region for the rotational transitions in the $v=9^{2}$ and $v=5^{1}$ excited $states^{a,b}$. Both effects are accounted for in the present line position and intensity calculations. For this study, in addition to the available literature $data ^{a,b,c}$ a large set of new high resolution FTS spectra recorded in Giessen were analysed and new centimeter measurements performed for $\nu_{5}$ and $2\nu_{9}$ rotational transitions in Kiel were used.
Description
$^{a}$T. M. Goyette, L. C. Oesterling, D. T. Petkie, R. A. Booker, P. Helminger and F. De Lucia, J. Mol. Spectrosc. 175, 395 (1996) $^{b}$D. T. Petkie, T. M. Goyette, P. Helminger, H. M. Pickett and F. De Lucia, J. Mol. Spectrosc. 208, 121 (2001) $^{c}$R. A. Toth, L. R. Brown, and E. A. Cohen, J. Mol. Spectrosc., in press (2003)
Author Institution: Laboratoire de Photophysique Mol\'{e}culaire, CNRS, Universit\'{e} Paris-Sud, Campus d'Orsay; Physikalisch-Chemisches Institut, Justus-Liebig-Universit\""{a}t; Physikalisch-Chemisches Institut, Institut f\""{u}r Physikalische Chemie; Department of Physics, The Ohio State University
Author Institution: Laboratoire de Photophysique Mol\'{e}culaire, CNRS, Universit\'{e} Paris-Sud, Campus d'Orsay; Physikalisch-Chemisches Institut, Justus-Liebig-Universit\""{a}t; Physikalisch-Chemisches Institut, Institut f\""{u}r Physikalische Chemie; Department of Physics, The Ohio State University