The absorption spectrum of HDO around 1.0 μm by ICLAS-VECSEL

The HDO absorption spectrum has been recorded between 9625 and 10 100 cm⁻¹ by intracavity laser absorption spectroscopy (ICLAS) based on a vertical external cavity surface emitting laser (VECSEL). Overall 1278 lines were attributed to the HDO species and were rovibrationally assigned using both the predictions based on the high-quality potential and dipole moment surfaces calculated by Schwenke and Partridge, and the spectrum simulation performed within the effective Hamiltonian approach. As a result, 289 precise energy levels were derived for the (1 0 2)-(0 2 2) resonance dyad and 101 were assigned to the (0 3 2), (2 3 0), (1 5 0), (3 1 0), (1 1 2), and (0 8 0) states. The effective Hamiltonian modeling of the (0 2 2)-(1 0 2) and (1 1 2)-(0 3 2) interacting dyads is presented and discussed. A few local perturbations with highly excited bending levels could be identified.