VIBRATIONAL SPECTRA OF PENTAFLUOROBROMOETHANE AND 1,1,2,2 TETRAFLUOROBROMOETHANE

Author Institution: Department of Physics, University of Oklahoma“The infrared spectra of gaseous $CF_{a}$ $CF_{2}Br$ and $CF_{2}H-CF_{2}Br$ and the Raman spectra of the liquids have been obtained at room temperature. All but two of the fundamental vibrational frequencies of $CF_{2}$ $CF_{2}Br$ have been assigned. Since $CF_{2}H-CF_{2}Br$ exhibits rotational isomerism, measurements of its infrared band intensities were made at different temperatures up to $185^{\circ} C$, and the infrared spectra of the liquid, at $-60^{\circ} C$, and solid, at $-170^{\circ} C$, were recorded. Also, the Raman spectrum of the liquid was observed at $-85^{\circ} C$. An attempt is being made to identify the fundamentals of the individual isomers. Preliminary measurements give 310 cal $deg^{-1}$ $mole^{-1}$ for $\Delta H^{0}_{0}$.