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The vibration-rotation spectra of the ν 1 and ν 8 fundamental bands of 32 SF 4 have been observed using Fourier-transform infrared spectroscopy. The band centre of the c -type ν 1 symmetric sulphur-equatorial-fluorine stretching vibration was observed at 891.6 cm -1 and that for the b -type ν 8 asymmetric sulphur-equatorial-fluorine stretching vibration at 864.6 cm -1 . In total, 2044 rovibrational transitions have been assigned. Analysis of the spectra showed that the rotational states of the ν 1 =1 and ν 8 =1 upper vibrational levels are coupled by an a -type Coriolis interaction. This coupling has been treated both using perturbation theory and by the explicit inclusion of an appropriate Hamiltonian matrix element in a combined fit of the data for both bands. Spectroscopic parameters have been determined for the ground, ν 1 =1 and ν 8 = 1 vibrational levels. Weaker transitions resulting from difference bands and the fundamental bands of the 34 SF 4 isotopomer have been identified but could not be assigned, because of the density of lines in the room-temperature spectrum. The possibility that discrepancies between the observed and predicted spectra of the ν 1 fundamental may result from either a Coriolis interaction with the states of another vibrational level, or the effects of intramolecular exchange of axial and equatorial fluorine atoms is considered. The discussion is supported by theoretical calculations which show that the likely path for intramolecular exchange is via a C 4v transition state. [ABSTRACT FROM AUTHOR]