First high resolution analysis of the 3ν2 and 3ν2−ν2 bands of 32S16O2

- High resolution analysis of S16O2 FTIR spectra.
- Hot transitions.
- Determination of spectroscopic parameters.

The second bending overtone band 3ν2 of sulfur dioxide has been studied for the first time with high resolution rotation-vibration spectroscopy. The 1530 transitions involving 728 upper state energy levels with Jmax.= 53 and Kamax.= 15 have been assigned to the 3ν2 band. The 746 transitions belonging to the 3ν2−ν2 “hot” band have been also assigned in the region of 950-1100  cm−1. For the analysis of the assigned transitions, an effective Hamiltonian of an isolated (030) vibrational state (the Watson operator in A-reduction and Ir representation) was used. Set of 9 varied parameters was determined which reproduce the initial experimental data with the drms deviations of 9.0×10−4 cm−1 and 9.8×10−4 cm−1 for the 3ν2 and 3ν2−ν2 bands, which are comparable with the experimental uncertainties.