Extended analysis of the high resolution FTIR spectra of H2MS ([formula omitted]) in the region of the bending fundamental band: The ν2 and [formula omitted] bands: Line positions, strengths, and pressure broadening widths

Abstract

The high resolution infrared spectra of hydrogen sulfide, H2MS (M=32,33,34,36) in the natural abundance (95.041% of H232S, 0.748% of H233S, 4.196% of H234S and 0.015% of H236S), were recorded with a Bruker IFS 125HR Fourier transform infrared spectrometer (Zürich prototype ZP2001) and analyzed in the ν2 fundamental band region (700 – 1800 cm−1). In the experimental spectra 1564, 1019, and 685 transitions were assigned to the ν2 bands of H232S, H234S and H233S (the maximum values of the quantum numbers are Jmax./Kamax. = 24/17, 20/14, 17/14). The subsequent weighted fits of experimentally assigned transitions were made with the Watson Hamiltonian and a set of parameters which reproduces the initial 333/249/216 infrared ro-vibrational energy values has been obtained from the assigned experimental line positions with the root mean square deviations of drms=2.2×10−4 cm−1,1.7×10−4 cm−1 and 1.5×10−4 cm−1 for the H232S, H234S and H233S isotopologues. Additionally, 703, 182 and 23 transitions with the values of quantum numbers Jmax./Kamax. = 18/14, 14/8 and 9/6 belonging to the 2ν2−ν2 hot bands of H232S, H234S and H233S (for the first time for the hot bands of the H234S and H233S species) were assigned in the experimental spectra. Rotational parameters of the ground vibrational state of H236S were re-determined, and, for the first time, 103 transitions (Jmax.=11,Kamax.=8) of the ν2 band of H236S were assigned in the experimental spectra. An analysis of ro-vibrational line strengths of 61 experimental isolated unsaturated and not too weak lines of the ν2 band of H232S was made (Jmax.=9,Kamax.=8), and five effective dipole moment parameters were obtained from the fit which reproduce the initial experimental line intensities with the drms = 1.4 %. An analogous analysis was performed for the H234S and H233S isotopologues. The half-widths analysis was made on the basis of the multi-spectrum fit with the Hartmann-Tran line profile, and self-pressure broadening coefficients were estimated for a few tens of lines for the three most abundant isotopologues.