The High-Resolution Spectrum of Water Vapor between 11 600 and 12 750 cm−1

Abstract

The absorption spectrum of water vapor has been recorded between 11 600 and 12 750 cm−1with a Fourier transform spectrometer (Kitt Peak, Az) at a resolution of 0.012 cm−1and with a path length of 434 m. The line assignment has led to the determination of 506 accurate energy levels of the (310) (211), (112), (013), (230), (131), (032), and (051) vibrational states which belong to the so-called 3ν + δ resonance polyad. The rotational energy levels obtained are on the average in agreement with those reported recently by R. Toth (J. Mol. Spectrosc.166,176–183 (1994)) for the strong bands, but there are differences for highJlevels or weak bands levels (about 15% of all levels). The experimental rotational energy levels have been fitted using Padé–Borel approximants and a set of 104 vibrational energies and rotational, resonance, and centrifugal distortion constants for the (310), (211), (112), (013), (230), (131), (032), and (051) vibrational states have been determined.