New interpretation of the far-infrared SO2 laser spectrum

Abstract

The ³²S¹⁶O₂ laser spectrum is definitively identified. The ten transitions observed involve the Fermi resonance which mixes the vibrotational levels 3ν₂,J_15,J−15 and ν₁+ν₂,J_13,J−13 of the ground electronic state, with J=29, 30, and 31. By using the value of 14.73 cm⁻¹ for the anharmonic constant k₁₂₂, the difference of the band centers (ν₁+ν₂)−(3ν₂) is obtained with great accuracy; it is equal to 114.59±0.01 cm⁻¹.