The eight first vibrational states of the water molecule: measurements and analysis

In this work the spectrum of the water molecule has been the subject of extensive experimental and theoretical investigations. More than 1500 transitions have been assigned in a far infrared emission spectrum recorded in the 50-500 cm⁻¹ region and experimental rotational energies have been obtained for the second triad of interacting states, (0 3 0), (1 1 0), and (0 1 1), up to J=10 using flame spectroscopy. These new data along with a large data set of already published experimental rotational energies, high-resolution infrared transitions, and microwave lines, involving the eight first vibrational states, have been analyzed using the theoretical formalism developed for water in a previous paper (J. Mol. Spectrosc. 206 (2001) 83), which accounts for the anomalous centrifugal distortion as well as for the Fermi- and Coriolis-type couplings.