title: CF₃CF₂N=S(F)CF₃: vibrational spectra and conformational properties.
abstract: The structural, conformational, and configurational properties of 1,1,1-trifluoro-N-(1,1,2,2,2-pentafluoroethyl) methanesulfinimidoyl fluoride, CF3CF2N=S(F)CF3 have been studied by vibrational spectroscopy [IR (vapor) and Raman (liquid)] and quantum chemical calculations [B3LYP, MP2 and B3PW91 levels of theory (using the 6-311+G(d) and 6-311+G(2df) basis sets). According to these theoretical approximations, CF3CF2N=S(F)CF3 might be found in the gas phase as a mixture of a favoured anticlinal form (C-N bond anticlinal with respect to the C-S-F bisector angle) and a less abundant syn conformer showing C1 symmetry as well (ΔG°≈1.5 kcal mol(-1)). However, corresponding vibrational modes for these conformers show only small shifts which would not allow confidently detecting the rather small contribution of this second form in the experimental spectra.
authors.affiliation: INQUINOA (CONICET-UNT) Instituto de Química Física, Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, San Lorenzo 456, 4000 Tucumán, Argentina.
authors.forename: Norma L
authors.initials: NL
authors.lastname: Robles
authors.affiliation: Institut für Physikalische und Theoretische Chemie, Universität Tübingen, 72076 Tübingen, Germany.
authors.forename: Heinz
authors.initials: H
authors.lastname: Oberhammer
authors.affiliation: Institut für Anorganische und Physikalische Chemie, Universität Bremen, 28334 Bremen, Germany.
authors.forename: Rüdiger
authors.initials: R
authors.lastname: Mews
authors.affiliation: INQUINOA (CONICET-UNT) Instituto de Química Física, Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, San Lorenzo 456, 4000 Tucumán, Argentina. Electronic address: cutin@fbqf.unt.edu.ar.
authors.forename: Edgardo H
authors.initials: EH
authors.lastname: Cutin
mesh_terms: D005459:Fluorides / Q000737:chemistry*; D008958:Models, Molecular; D008968:Molecular Conformation; D011789:Quantum Theory; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman; D013816:Thermodynamics; D014732:Vibration
chemical_list: D005459:Fluorides
keywords: 1,1,1-Trifluoro-N-(1,1,2,2,2-pentafluoroethyl) methanesulfinimidoyl fluoride; Conformational equilibrium; Quantum chemical calculations; Vibrational spectroscopy