The infrared absorption spectrum of SF₅CF₃ was studied at 296 K over a more extensive wavenumber range (100-4000 cm^-1 using spectral resolutions of 0.01 and 0.90 cm^-1) than had previously been reported. There was no discernable effect of spectral resolution on the measured IR spectra. Over the region for which comparison can be made (700-1400 cm^-1) the absorption cross-sections were indistinguishable within the experimental uncertainties (±5%) from those reported by Sturges et al. (Science 289 (2000) 611). The absorption feature at 612.5 cm^-1 which was not reported by Sturges et al. (2000) was quantified in the present work. Inclusion of this feature increases the global-mean forcing due to SF₅CF₃ by about 3.5% to 0.59 W m^-2ppbv^-1 and reinforces the position of SF₅CF₃ as the most powerful greenhouse gas, per molecule, yet detected in the atmosphere. The 100-yr mass-normalized global warming potential of SF₅CF₃, relative to CO₂ is 19,000.