The ν 1, ν 2, and ν 3 bands of carbonyl chlorofluoride (COFCl) at 5.3, 9.1, and 13.1 μm: position and intensity parameters and their use for atmospheric studies

Abstract

A list of line positions and, for the first time, of line intensities was generated for the ν 1, ν 2, and ν 3 fundamental bands of the 12C 16OF 35Cl and 12C 16OF 37Cl isotopologs of carbonyl chlorofluoride, located at 5.3, 9.1, and 13.1 μm, respectively. In addition, for the most abundant isotopolog ( 12C 16OF 35Cl) this linelist includes also the contributions from the first two associated hot bands. The parameters included in this database were generated by combining the results of previous experimental analyses and ab initio calculations [Perrin A, Flaud JM, Bürger H, Pawelke G, Sander S, Willner H. First high resolution analysis of the six fundamental bands ν 1, ν 2, ν 3, ν 4, ν 5 and ν 6 of COF 35Cl in the 340 to 2000 cm −1 region. J Mol Spectrosc 2001;209:122–232; Demaison J, Perrin A, Bürger H. Ab initio anharmonic force field and equilibrium structure of carbonyl chlorofluoride. J Mol Spectrosc 2003;221:47–56]. For the purpose of the present work, a partial re-investigation of the ν 1 of COF 35Cl was performed, together with the first identification of the ν 2 band of COF 37Cl. These parameters were generated in order to improve the quality of remote sensing of the atmosphere in the mid-IR. Analyses of atmospheric solar occultation spectra measured by the JPL MkIV interferometer show that the new linelist not only improves the quality of retrievals of COFCl, but also of several other gases whose absorptions overlap those of COFCl.