THE $\nu_{3}$ AND $\nu_{4}$ INFRARED BANDS OF $SF_{6}$

Author Institution: Los Alamos Scientific LaboratoryThe $\nu_{3}$ band at 948 $cm^{-1}$ and the $\nu_{4}$ band at 615 $cm^{-1}$ of $SF_{6}$ have been observed at high resolution using a tunable semiconductor laser diode. The sample was cooled to about $135^{\circ} K$ to remove thermally excited vibrational species. The $\nu_{3}$ band exhibits considerable high order splitting of the individual rotational lines and a Q branch which has little regular structure. The splitting is much less striking in the $\nu_{4}$ band. An analysis of the spectra for molecular constants is presented