High resolution analysis of the (111) vibrational state of SO2

- The first high resolution analysis of the very weak band, ν1+ν2+ν3.
- Increasing more than three times information about the ν1+ν2+ν3−ν2 band than was known before.
- Determination and improvement of spectroscopic parameters of the (111) state.

The high resolution Fourier transform spectrum of the weak ν1+ν2+ν3 band was recorded and analyzed for the first time. 1085 transitions with values of quantum numbers Jmax.=65 and Kamax.=21 were assigned to that band. The hot band ν1+ν2+ν3−ν2 was also recorded and analyzed, and 1132 transitions with values of quantum numbers Jmax.=77 and Kamax.=20 were assigned. On the basis of the obtained information, 780 ro-vibrational energies of the (111) upper vibrational state were determined. The derived results significantly exceed analogous results known in the literature both in number of the assigned transitions and upper energy levels, and in values of quantum numbers Jmax. and Kamax..