Stimulated emission pumping to the rotationally resolved state υ = (0, 22, 0) of the ground electronic state of CS 2 by three-level polarization spectroscopy

Abstract

Stimulated emission pumping to the rotationally resolved state v = (0, 22, 0) of X 1Σ + g of CS 2 has been achieved by three-level polarization spectroscopy. The spectra thus obtained are regular at these high vibrational quanta. Being perturbed by high-order terms of potential function, such as Fermi resonance, both parallel and perpendicular bands appeared with significant intensity in the spectra. The molecule exhibited the properties of a slightly asymmetric top in this state. The anomalous positions of Δ K = 0 and Δ K = − 1 bands indicate that the molecule suffers a strong vibrational—rotational interaction. The Coriolis force terms have been taken into account in the data analysis. With the apex angle 2α = 147.6°, the rotational constants are A v = 4.860 cm −1, B v = 0.11195 cm −1, and C v = 0.11105 cm −1.