The infrared absorption spectrum of gaseous 1,1,1-trifluoro-2-chloro-2-bromoethane has been obtained with a 1-m cell and a Perkin-Elmer double-pass spectrometer equipped with CsBr, NaCl, and LiF prisms. The Raman spectrum of the liquid phase has been photographed with a 3-prism glass spectrograph of reciprocal linear dispersion 15 A/mm at 4358 A. The 18 vibrational fundamentals have been assigned as follows: 72, 160, 202, 229, 310, 364, 520, 552, 665, 718, 814, 863, 1133, 1179, 1198, 1273, 1313, and 3017 cm—1. The four lowest are for the liquid state, the others for the gas. The spectra have been interpreted in detail. Thermodynamic functions have been calculated.