The Water Molecule: Line Position and Line Intensity Analyses up to the Second Triad
| Main Authors: | Coudert, L. H., Wagner, G., Birk, M., Flaud, J.-M. |
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| Format: | info Proceeding Journal |
| Terbitan: |
, 2006
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| Subjects: | |
| Online Access: |
https://zenodo.org/record/17620 |
Daftar Isi:
- With a view towards building a highly accurate database for the water molecule in the 1000 to 2000 cm -1 region, line position and line intensity analyses of a large body of high-resolution data were carried out. For both analyses, the bending-rotation theoretical approach 1 was used. The body of data fitted in the line position analysis consists of experimental energies as well as microwave, FIR, and IR transitions. In the line strength analysis, experimental line intensities were fitted. For both analyses, the data involve the first eight vibrational states of water, that is, all the vibrational states up to the second triad. In the first part of the paper, the results of the line position analysis will be reported and the inclusion in the data set of the recent microwave measurements of Matsushima et al. 2 will be discussed. The second part of the paper we will devoted to the line strength analysis. The results obtained fitting the new measurements of Toth 3 , concern- ing transitions involving one the states of the second triad, will be reported. Although the results of both the line position and the line intensity analyses are satisfactory, they indicate that there are inconsistencies within and between the various sets of of data. This is certainly the case of the line intensity data for transitions belonging to the ? 2 band, which is the band for which there is the largest amount of data. For this band the measurements reported by Toth 4 are available as well as the recent ones carried out at DLR. Depending on the set of data being considered, the observed minus calculated residuals, in % of the observed strength, do not display the same behavior when the strength increases from 10 -25 to 10 -19 cm -1/molecule ú cm -2 . This behavior will be given for the line strengths reported by Toth 4 and for those measured in the present work. Issues addressing the data quality and reasons for the di’erences of the data sets will be discussed.