High-resolution infrared spectra of the v6 (713 cm−1) band region of C2F6 vapor have been recorded at several temperatures. Spectra at 77, 200, and 300 K were recorded using a Fourier transform spectrometer with unapodized resolutions of 0.0018 cm−1 (200 and 300 K) and 0.008 cm−1 (77 K). Spectra with rotational temperatures in the range 5-50 K were recorded in a supersonic jet using diode-laser absorption spectroscopy. The v6 band contains two clear sequences of hot-bands: one arises from the v4 torsional vibration at 67.5 cm−1; the other, shorter, weaker progression is built on the doubly degenerate v9 vibration at 220 cm−1. They lie to high and low wavenumbers of the fundamental band, respectively. Eleven series were assigned and fitted to these hot bands. A perturbed series in the v4 sequence is considered, by analogy with the infrared spectrum of C2H6 vapor, to be caused by an xy-Coriolis interaction either between 5v4 and v9 + 2v4 in the ground state or, in the upper state, v6 + 5v4 with v6 + v9 + 2v4 or v6 + 5v4 with 2v8. One further series resolved only in the jet spectrum and lying very close to the fundamental is almost certainly due to the v6 fundamental of the isotopomer 13C12CF6.
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