On the 3$^{1}\Pi_{u}$ state in caesium dimer

TL;DR

This study used polarisation labelling spectroscopy to investigate the 3$^{1}\Pi_{u}$ state of the Cs$_2$ molecule, determining key constants and vibrational levels, revealing strong perturbations by neighboring states.

Contribution

It provides new spectroscopic data and detailed analysis of the 3$^{1}\Pi_{u}$ state in cesium dimer, including equilibrium constants and vibrational levels, with insights into perturbations.

Findings

Determined equilibrium constants: $T_e=20684.60$cm$^{-1}$, $\omega_e=30.61$cm$^{-1}$, $R_e=5.27$Å.

Identified vibrational levels $v=4-35$ and their perturbations.

Mapped 3094 rovibronic levels in the perturbed complex.

Abstract

Polarisation labelling spectroscopy technique was employed to study the 3$^{1}\Pi_{u}$ state of Cs$_2$ molecule. The main equlibrium constants are $T_e=20684.60$cm$^{-1}$, $\omega_e=30.61$cm$^{-1}$ and $R_e=5.27$\r{A}. Vibrational levels $v=4-35$ of the 3$^{1}\Pi_{u}$ state were found to be subject to strong perturbations by the neighbouring electronic states. Energies of 3094 rovibronic levels of the perturbed complex were determined.