In this paper, the measurement of the energy difference between the rotational conformers of 1-2-diiodotetrafluoroethane by GC/FT-IR spectroscopy is demonstrated for the first time. The ΔH° obtained is lower than the value reported from the use of the neat vapor-phase method. The difference between the values may be attributed to solvent and adsorption effects.
J. Liang, D. Drake, and M. Roselius, "Conformer Analysis Study of 1,2-Diiodotetrafluoroethane by Gas Chromatography/Fourier Transform Infrared Spectroscopy," Appl. Spectrosc. 48, 206-208 (1994)