Calculation of the temperature dependence of the multiphoton absorption spectrum of SF_6

Abstract

The temperature dependence of the theoretical multiphoton absorption spectrum of SF6 gas is obtained by forming a superposition of ν3-ladder spectra properly shifted and weighted by the vibrational Boltzmann factor for temperatures of 150 and 300 K. First-order rotational effects are included, and all levels up to three-photon absorption are contained in the model. Over 70 hotbands (95% of total population) are included at 300 K. The calculations show general broadening and a red shift to the absorption spectrum at room temperature, which is not, however, great enough to account for the experimentally observed dissociation-rate spectrum. We conclude that resonant absorption in the quasi-continuum occurs at or below 940 cm−1.