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First High-Resolution Analyses of the Ņ8 and Ņ8 + Ņ9 Spectral Regions of 35 CIONO2: Determination of the Ņ9 Band Centre



J.- M. Flaud, Walter J. Lafferty, J Orphal, M Birk, G Wagner


A ro-vibrational analysis of the C-type Ņ8 fundamental band of 35CIONO2 as well as the hot band, Ņ8 + Ņ9 - Ņ9, has been carried out using a Fourier-transform infrared spectrum of natural chlorine nitrate recorded with a resolution of 0.0094 cm-1 at a temperature of 190K. Accurate upper state constants have been determined for both bands including following band centers: Ņ08) = 711.20763(9) and Ņ089) = 714.9050(12)cm-1. These constants have been used, together with a transition moment operator which takes into account the observed Herman-Wallis effect, to successfully model the experimental spectrum. In addition, the constants of the 8191 state have been used to model the Ņ8 + Ņ9 band, allowing us to assign nearly 100 Q-branch transitions and, therefore, to determine the band center of the Ņ8 + Ņ9 band, Ņ089) = 838.6369(15) cm-1. Consequently this allows us to obtain the band center of Ņ9: Ņ09) = 123.7219(20) cm-1. This establishes unambiguously that the band at 714.9 cm-1 previously attributed to Ņ5 + Ņ7 - Ņ9 is actually the Ņ8 + Ņ99 hot band.
Molecular Physics


chlorine nitrate, Herman-Wallis effect, high-resolution infrared spectrum, line intensities, rotation constants


Flaud, J. , Lafferty, W. , Orphal, J. , Birk, M. and Wagner, G. (2003), First High-Resolution Analyses of the &#325;<sub>8</sub> and &#325;<sub>8</sub> + &#325;<sub>9</sub> Spectral Regions of <sup>35</sup> CIONO<sub>2</sub>: Determination of the &#325;<sub>9</sub> Band Centre, Molecular Physics (Accessed December 8, 2023)
Created April 30, 2003, Updated October 12, 2021