HDO absorption spectrum above 11 500 cm−1: Assignment and dynamics

Assignment of an HDO line list extracted from a recently measured H2O/HDO/D2O Fourier transform absorption spectrum recorded in the 11 600-23 000 cm−1 region by Bach et al. (M. Bach, S. Fally, P.-F. Coheur, M. Carleer, A. Jenouvrier, A.C. Vandaele, J. Mol. Spectrosc. 232 (2005) 341-350.) is presented. More than 94% of the 3256 lines are given quantum number assignments and ascribed to line absorption by HDO; most of the remaining lines are actually due to D2O. High accuracy variational predictions of line positions and intensities are used for the spectral assignment process. Assignments to the ν1 + 5ν3, 2ν2 + 5ν3, ν1 + ν2 + 3ν3 and ν1 + 6ν3 bands are presented for the first time. Comparisons are made with published ICLAS spectra covering the same spectral region and suggestions made for its recalibration. The results are used to illustrate the dynamical behaviour of highly excited vibrational states of HDO and to discuss previous vibrational assignments to high lying rotation-vibration states of this system.