Detection and analysis of three highly excited vibrational bands of 16O3 by CW-CRDS near the dissociation threshold

- Cavity ring down spectroscopy of 16O3 between 7600 and 7920 cm−1.
- 531 Transitions assigned to three vibrational bands.
- Upper vibrational states located only a few % below the dissociation limit.
- Effective operator modelling of the spectra.
- Good agreement with ab initio values for the band centres and rotational constants.

The present contribution is devoted to the analysis of three extremely weak A-type bands of 16O3 recorded near 7686, 7739 and 7860 cm−1i.e. only a few % below the dissociation limit, D0, at about 8560 cm−1. They correspond to the most excited vibration-rotation states of ozone observed so far via high-resolution absorption spectroscopy. They were detected by high sensitivity CW-cavity ring down spectroscopy with a typical noise equivalent absorption, αmin, on the order of 2×10−10 cm−1 and modelled using the effective operator approach. The derived band centres and rotational constants show a very good agreement with recent theoretical predictions based on a new ab initio potential energy surface.