Analysis of 3ν3 in SF6

Abstract

Studies of the 3ν₃ absorption band in SF₆ in the spectral region from 2800 to 2850 cm⁻¹ have been completed with a FT–IR spectrometer at a spectral resolution of 0.04 cm⁻¹. This study confirms the results reported earlier by Kildal on the general shape of this absorption band. The absorption has been studied as a function of temperature, allowing a definite assignment to be made of the ground state features observed in this spectrum at room temperature. The ground state absorption to 3ν₃ appears with a double Q branch [estimated band origins at 2830.22 and 2827.62 (±0.06) cm⁻¹]. The intensities and temperature dependence studies confirm the assignment by Fox of these two Q branches to the two F_1u components of the 3ν₃ state.