On the 31Πu state in caesium dimer

Abstract Polarisation labelling spectroscopy technique was employed to study the 3 1 Π u state of Cs2 molecule. The main equlibrium constants are T e = 20684.56 cm - 1 , ω e = 30.62 cm-1 and R e = 5.27 A. Vibrational levels v = 4 - 35 of the 3 1 Π u state were found to be subject to strong perturbations by the neighbouring electronic states. Energies of 3352 rovibronic levels of the perturbed complex were determined.