Observation of b$_2$ symmetry vibrational levels of the SO$_2$ $\tilde{\mbox{C}}$ $^1$B$_2$ state: Vibrational level staggering, Coriolis interactions, and rotation-vibration constants

G. Barratt Park; Jun Jiang; Catherine A. Saladrigas; Robert W. Field

doi:10.1063/1.4944924

paper

Observation of b $_{2}$ symmetry vibrational levels of the SO $_{2}$ $\tilde{\mbox{C}}$ $^{1}$ B $_{2}$ state: Vibrational level staggering, Coriolis interactions, and rotation-vibration constants

arXiv:1604.06817 · doi:10.1063/1.4944924

Abstract

The $C ~$ $^{1}$ B $_{2}$ state of SO $_{2}$ has a double-minimum potential in the antisymmetric stretch coordinate, such that the minimum energy geometry has nonequivalent SO bond lengths. However, low-lying levels with odd quanta of antisymmetric stretch (b $_{2}$ vibrational symmetry) have not previously been observed because transitions into these levels from the zero-point level of the $X ~$ state are vibronically forbidden. We use IR-UV double resonance to observe the b $_{2}$ vibrational levels of the $C ~$ state below 1600 cm $^{- 1}$ of vibrational excitation. This enables a direct characterization of the vibrational level staggering that results from the double-minimum potential. In addition, it allows us to deperturb the strong $c$ -axis Coriolis interactions between levels of a $_{1}$ and b $_{2}$ vibrational symmetry, and to determine accurately the vibrational dependence of the rotational constants in the distorted $C ~$ electronic state.

Observation of b2​ symmetry vibrational levels of the SO2​ $\tilde{\mbox{C}}$ 1B2​ state: Vibrational level staggering, Coriolis interactions, and rotation-vibration constants

Abstract

Observation of b $_{2}$ symmetry vibrational levels of the SO $_{2}$ $\tilde{\mbox{C}}$ $^{1}$ B $_{2}$ state: Vibrational level staggering, Coriolis interactions, and rotation-vibration constants