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Published on: December 18, 2015
Water Vapor Line Assignments in the Near Infrared
1Department of Physics and Astronomy, University College London, Gower Street, London, WC1E 6BT, United Kingdom
Journal of Molecular Spectroscopy
|December 16, 1998
Summary
This study analyzes the high-resolution spectrum of water vapor, assigning hundreds of previously unassigned spectral lines. This research enhances our understanding of water vapor
Area of Science:
- Molecular Spectroscopy
- Quantum Chemistry
- Atmospheric Science
Background:
- High-resolution spectra provide critical data for understanding molecular behavior.
- Previous analysis of water vapor spectra left many lines unassigned.
- Accurate spectral data is essential for atmospheric modeling and remote sensing.
Purpose of the Study:
- To assign previously unassigned lines in the high-resolution water vapor spectrum.
- To improve the accuracy and completeness of water vapor spectral databases.
- To extend the measured data for specific vibrational polyads and bands.
Main Methods:
- Analysis of high-resolution water vapor spectra (13,200–16,500 cm−1).
- Utilized high-accuracy ab initio calculations and spectroscopically determined potentials.
- Employed combination differences for assignment and reassignment validation.
Main Results:
- Assigned 663 of 795 unassigned H216O lines.
- Reassigned 38 existing lines.
- Provided first-time spectral information for several vibrational bands, including (240), (033), (160), (170), and (071).
Conclusions:
- The assignments significantly extend the available spectral data for water vapor.
- A substantial portion of remaining unassigned lines likely belong to the H218O isotopologue.
- This work refines our understanding of water vapor spectroscopy.
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