PRESSURE BROADENING IN THE $\nu_{1}$ AND $\nu_{3}$ BANDS OF $H_{2}S$

Abstract

We present measurements of the broadening coefficient of absorption lines from the $\nu_{1}$ and $\nu_{3}$ bands of $H_{2}S$ in the wavenumber region between $2690 cm^{-1}$ and $2765 cm^{-1}$ measured with a diode laser spectrometer. These bands are of great interest because of the strong Coriolis interaction between the $\nu_{1}$ and $\nu_{3}$ bands as well as between the $2\nu_{2}$ and $\nu_{3}$ bands and additionally the Fermi interaction between the $2\nu_{2}$ and $\nu_{1}$ bands. Due to the weakness of these bands we had to apply a Herriott multipass cell with a path length of 4.7 m. The study includes 24 lines of the $\nu_{1}$ band with $3 \leq J^{\prime\prime} \leq 17, 0 \leq K_{a}^{\prime\prime} \leq 7$ and 6 lines of the $\nu_{3}$ band with $3 \leq J^{\prime\prime}\leq 7, 1 \leq K_{a}^{\prime \prime} \leq 7$. As perturbers we used $H_{2}S, N_{2}$, air, He, Ne, Ar, Kr, and Xe. We will discuss the quantum number dependence of the broadening coefficients and compare the results with those in the case of $SO_{2}$ where only weak interactions occur.