High sensitivity absorption spectroscopy of HDO by ICLAS-VeCSEL between 9100 and 9640 cm

The absorption spectrum of monodeuterated water has been recorded between 9100 and 9640 cm⁻¹ using intracavity laser absorption spectroscopy (ICLAS) based on a vertical external cavity system emitting laser (VeCSEL). Overall 1706 lines were attributed to the HDO species. The spectrum assignment was performed on the basis of the ab initio calculations by Schwenke and Partridge. A set of 746 energy levels was derived from transitions assigned to 13 upper vibrational states, 300 of them being reported for the first time. Resonance interactions leading to an important strengthening and observations of the very weak 7ν₂ and ν₁ + 5ν₂ bands are discussed. A detailed line list has been generated.