Internal rotation in trifluoromethylsulfur pentafluoride: CF 3SF 5 by Fourier transform microwave spectroscopy

摘要

Graphical abstractDisplay OmittedAbstractTrifluoromethylsulfur pentafluoride CF3SF5, which has been attracting much attention because of its unusually large global warming potential, was investigated by Fourier transform microwave spectroscopy in order to determine the twelve-fold potential barrier to internal rotation in this molecule. We have found theV12value to be close to zero. Relaxation among internal-rotation and overall-rotation levels was found inhomogeneous, resulting in distributions quite different from thermal in low-temperature molecular beam, which might affect significantly thermodynamic properties of the molecule. Rotational spectra of the13C species and the34S species were also observed in natural abundance, leading to thersCS bond length of 1.8808 (7) ?.]]>