Extended FTIR high resolution analysis of hydrogen sulfide in the region of the second hexad: Line positions and ro–vibrational energies of H[formula omitted]S ([formula omitted

Abstract

The high resolution infrared spectra of hydrogen sulfide H232S were recorded with a Bruker IFS 125HR Fourier transform infrared spectrometer (Zürich prototype ZP2001) and analyzed in the region of 5650–6660 cm−1 where six interacting bands (2ν1+ν2,ν1+ν2+ν3,ν1+3ν2,3ν2+ν3, 5ν2 and ν2+2ν3) of the second hexade are located. 2452 transitions with maximum values of the quantum numbers Jmax = 18/19/13/14/14/11 and Kamax = 10/11/8/11/7/5 were assigned in the experimental spectra to the 2ν1+ν2,ν1+ν2+ν3,ν1+3ν2,3ν2+ν3, 5ν2 and ν2+2ν3 bands. On this basis, 194/216/108/104/90/9 upper ro–vibrational energies (more than 1.4 times higher number of both transitions and upper energy values compared to the preceding studies) were obtained for the upper vibrational states (210), (111), (130), (031), (050) and (012). These data were used in the weighted fit of the Watson Hamiltonian parameters. The 172 parameters obtained from the fit reproduce the 721 initial energy values of six vibrational states (2452 transitions) with the root mean square deviation drms=7.1×10−4 cm−1. The 534 transitions belonging to the 2ν1+ν2 and ν1+ν2+ν3 bands of H234S (197 upper energy values; about 1.5 times higher number for the ν1+ν2+ν3 band and more than two times higher number for the 2ν1+ν2 band) were recorded and analysed. For the first time, 177 transitions (70 upper energy values) were assigned to the ν1+ν2+ν3 band of H233S.