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HFC-43-10mee (C5H2F10) is a substitute for CFC-113, HCFC-141b and methyl chloroform, as well as an alternative to perfluorocarbons with high radiative efficiencies. Recent observations have shown that the global mean tropospheric abundance of HFC-43-10mee has increased steadily from the 1990s to reach 0.211 ppt in 2012. To date, the emission of this compound is not regulated. The radiative efficiency (RE) of HFC-43-10mee has recently been re-evaluated at 0.42 W m−2 ppb−1, giving a 100-year time horizon global warming potential (GWP100) of 1650. However, the initial RE, from which the new values were derived, originated from an unpublished source. We calculated a new RE of 0.36 W m−2 ppb−1 and a GWP100 of 1410 from laboratory absorption cross-section spectra of a pure vapour of HFC-43-10mee. Acquisitions were performed in the 550–3500 cm−1 spectral range using Fourier transform spectroscopy. The results were compared with the broadened spectra from the Pacific Northwest National Laboratory (PNNL) database and with theoretical calculations using density functional theory.

Composite absorption cross-sections of the hydrofluoroether HFE-347pcf2 (CAS number 406-78-0) have been determined from experimental and theoretical data. The experimental cross-sections have been used as a gauge to evaluate the accuracy of computational data obtained from different density functional theory methods. The B3LYP functional with a small 6-31G(d) basis set was found to provide the best results. A simulated spectrum was added to our experimental data to calculate the radiative efficiency and global warming potential of the molecule over the entire atmospheric spectral window. We found a radiative efficiency of 0.46 Wm−2ppb−1 and a 100-year global warming potential of 980.

Cross-sections of perfluorotributylamine (PFTBA) were derived from Fourier transform spectroscopy at 570–3400 cm −1 with a resolution of 0.1 cm −1 over a temperature range of 298–344 K. These results were compared to theoretical density functional theory (DFT) calculations and to previous measurements of PFTBA made at room temperature. DFT calculations were performed using the B3LYP method and the 6-311G(d,p) basis set. We find good agreement between our experimentally derived results, DFT calculations, and previously published data. No significant temperature dependence in the PFTBA cross-sections was observed for the temperature range studied. We calculate an average integrated band strength of 7.81 × 10 −16 cm/molecule for PFTBA over the spectral range studied. Radiative efficiencies (RE) and global warming potentials (GWP) for PFTBA were also derived. The calculated radiative efficiencies show no dependence on temperature and agree with prior publications. We find an average RE of 0.77 Wm −2 ppbv −1 and a range of GWP from 6874 to 7571 depending on the lifetime used. Our findings are consistent with previous studies and increase our confidence in the value of the GWP of PFTBA.

Experimental absorption cross-section spectra of HFE-356mec3 (CH3OCF2CHFCF3) have been acquired at three temperatures and at a resolution of 0.1 cm−1 over the spectral range 550–3500 cm−1. The results have been completed with theoretical calculations using density functional theory and ab initio methods at different levels of theory. A lifetime-corrected radiative efficiency of 0.31 Wm−2ppb−1 was obtained, leading to a 100-year time horizon global warming potential of 260 using an atmospheric lifetime of 2.5 years.

Altitude-resolved volume mixing ratio profiles of CFC-113 have recently become available on a global scale with the Atmospheric Chemistry Experiment (ACE) satellite mission. However, the accuracy of the retrieval is currently limited by the uncertainties on the spectroscopic parameters of CFC-113. This paper reports on the geometrical structure, harmonic frequencies and intensities in the mid-infrared region of the two conformers of CFC-113 and the evaluation of whether theoretical calculations reproduce measurements. The calculations are performed using density functional theory at the B3LYP/6-311+G(3df) level. The molecular geometry parameters, the enthalpy difference and the potential barrier between conformers are calculated. The harmonic frequency of the normal modes of vibration are presented and accurately compared to experimental data. Overtones and combination bands are assigned in the 1200– 2500 cm � 1 region.