Sulfur tetrafluoride methylimide, CH3NSF4: Vibrational spectra and quantum chemical calculations

Infrared (gas) and Raman (liquid) spectra of sulfur tetrafluoride methylimide, CH3NSF4, were recorded and interpreted. Structural, vibrational and configurational properties were derived from quantum chemical calculations [HF, MP2 and B3LYP methods with 6-311+G(2df,p) basis sets]. The assignment of the normal modes of vibrations was carried out by comparison with analogous molecules and with calculated frequencies and intensities. All theoretical approaches predict the existence of a unique form in the fluid phases which possesses CS symmetry, in good agreement with experimental results.