First far-infrared high-resolution analysis of the nu(2) band of sulphur dioxide (SOO)-S-32-O-16-O-18 and (SO2)-S-32-O-18

摘要

High-resolution Fourier transformpectra of O-18-enriched isotopic samples of sulphur dioxide' ((SOO)-S-32-O-16-O-18 and (SO2)-S-32-O-18) have been recorded at 0.00102 cm(-1) resolution In the 400-620 cm(-1) region. at Synchrotron SOLEIL These spectra have been recorded at low temperature 185 K using a 314 rn pt cal path length cryogenic cell. This enables the first detailed infrared analysis of the nu(2) bands o h and 3251802 isotopologues of Hamiltonian dioxide located at 50736541(1) and 496,599880 Cmmm1 respectively. Usinga Watson-type Hamiltoma model to compute the upper and lower state energy levels, it was passible to reproduce the observed transitions. For both species, accurate rota ional and centrifugal distortion constants were derived for the, upper (0,1,0) vibrational state,while' hose of the (0,0,0) ground state were significantly updated. For this task, we combined the results' of he present infrared measurements with the available fiterature microwave datain the (0 0,0) and) vibrational states. Finally, we took the opportunity of this study to compare t hequality f he fit using an A- and S-type reduction for the Watson Hamiltonian.