Analysis of New Measurements of 18O-substituted Isotopic Species 16O16O18O and 16O18O16O of Ozone in the THz and Far-Infrared Ranges

Abstract

High-resolution spectra corresponding to the rotational and the ν₂–ν₂ bands of the two most abundant isotopic species of ozone with one heavy ¹⁸O oxygen atom were recorded using SOLEIL synchrotron radiation source in the range 30–200 cm⁻¹. Additionally, the ν₂ vibrational-rotational bands were recorded between 550 and 880 cm⁻¹ using a classical glowbar source that made it possible to extend and refine information compared to published data on the observed transitions of these bands. The analyses of recorded spectra permitted us to deduce experimental set of energy levels for the ground (000) and the first bending (010) vibrational states, which significantly exceeds literature data in terms of rotational quantum numbers. For both isotopic species, the weighted fits of all experimental line positions were carried out including previously published microwave data. As a result of this work, the improved values of rotational and centrifugal distortion parameters for the states (000) and (010) were obtained that permitted modelling the experimental line positions with a weighted standard deviation of 1.284 (2235 transitions) and 0.908 (4597 transitions), respectively, for ¹⁶O¹⁶O¹⁸O, and 1.168 (824 transitions) and 1.724 (2381 transitions) for ¹⁶O¹⁸O¹⁶O.