First determination of the NO2 Ã 2B2 stretching frequencies by jet cooled intracavity laser absorption spectroscopy around 11 000 cm−1

摘要: Using intracavity laser absorption spectroscopy combined with a supersonic slit jet, we have observed and analyzed seven vibronic cold bands of NO2 between 10 800 11 680 cm−1. The energies, relative intensities, A, B, C rotational constants, the spin-rotation constants been determined. play crucial role in assignments. states are vibronically mixed. However, three them dominant A 2B2 electronic character while four others X 2A1 character. vibrational assignments energies levels are: (1, 0, 0) at 10 999.42 cm−1, (0, 2, 11 210.50 cm−1, 2) 11 283.15 cm−1. frequencies symmetric stretch, (ω1≅1265 cm−1), bending, (ω2≅738 cm−1) modes derived from agreement ab initio calculations. In contrast, frequency antisymmetric ω3≅775 cm−1, level, ...