The 626M24 dataset of validated transitions and empirical rovibrational energy levels of 16O12C16O

The 626M24 dataset created during this project contains validated experimental transitions and empirical rovibrational energy levels for the parent carbon dioxide isotopologue, ¹²C¹⁶O₂ (in a shorthand notation, 626). Validation of the measured transitions and determination of the empirical energy levels is based on a compiled and carefully checked dataset of experimental rovibrational transitions collected from 143 literature sources. The 44 828 measured lines collected, in the wavenumber range of 42.9 - 14 076 cm^-1, describe 22 218 unique transitions. Inversion of the experimental information yields 8268 empirical rovibrational energy levels for 626, with uncertainty estimates compliant with the experimental uncertainties of the transitions. Comparison with the Carbon Dioxide Spectroscopic Databank (CDSD-296), NASA Ames-2021, and HITRAN2020 line catalogues shows generally good agreement and suggests some possible improvements to these databases. The 626M24 dataset and an extended line list, called 626M24LL, built upon it and containing 285 503 line positions, are deposited in an OSF (Open Science Framework) repository.