CF3CF2N=S(F)CF3: Vibrational spectra and conformational properties

NORMA L. ROBLES; HEINZ OBERHAMMER; RÜDIGER MEWS; EDGARDO CUTIN

SPECTROCHIMICA ACTA A: MOLECULAR AND BIOMOLECULAR SPECTROSCOPY

ELSEVIER

Lugar: Amsterdam; Año: 2014 vol. 125 p. 1 - 6

0584-8539

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 (DeltaG = 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.