Spectroscopic and theoretical studies of sulfamoil fluoride, FSO2NH2 and N-(fluorosulfonyl) imidosulfuryl fluoride, FSO2NS(O)F2

FT-IR and Raman spectra of sulfamoil fluoride, FSO2NH2, and N-(fluorosulfonyl) imidosulfuryl fluoride, FSO2NS(O)F-2, were obtained. The experimental data are compared to results of ab initio and density functional theory (DFT) calculations. According to the theoretical studies the main conformer of FSO2NH2 possesses anti conformation (F-S single bond in anti position with respect to the nitrogen lone pair). The vibrational spectra do not confirm the presence of a second conformer in the gas and liquid phases. They have been interpreted on the basis of C-s symmetry. The Raman spectra of the liquid and the gas infrared spectra of FSO2NS(O)F-2 have been interpreted in the terms of the existence of a single conformation possessing C-1 symmetry, as determined previously by gas electron diffraction (GED). An assignment of the observed bands is proposed for both molecules. (C) 2003 Elsevier B.V. All rights reserved.