Study of the high resolution spectrum of 32S16O18O: The ν1 and ν3 bands

•High resolution analysis of the ν1/ν3 bands of S16O18O.•Resonance interactions.•Determination of spectroscopic parameters.

The high resolution infrared spectrum of the 32S16O18O molecule was recorded for the first time with a Bruker IFS 120 HR Fourier transform interferometer in the region of 930-1580 cm−1 where the bands ν1 and ν3 are located. More than 3000 and about 2400 transitions were assigned in the experimental spectrum with the maximum values of quantum numbers Jmax./Kamax. equal to 58/23 and 68/23 to the bands ν1 and ν3, respectively. The further weighted fit of experimentally assigned transitions was made with the Hamiltonian model which takes into account Coriolis resonance interaction between the vibrational states (100) and (001). The 81 microwave transitions of the states (100) and (001) known from the literature also were taken into account. As the result, a set of 26 fitted parameters was obtained which reproduces the experiment-based 2690 ro-vibrational energy values of the two bands with the drms=1.8×10−4cm−1. Microwave transitions are also reproduced with the accuracy close to experimental uncertainty.