The vibrational constant of the O 22+ X 1Σ g+ state from the dissociative decay of n = 3, 4 Rydberg states in O 2+

Abstract

Experimental data are presented on the vibrational constant of the O 2 2+ X 1Σ g + ground state. Fast O 2 2+ ions undergo charge transfer collisions with cesium or magnesium atoms. Product, singly charged, ions are formed in molecular Rydberg states. It is argued that (3sσ) O + 2 Rydberg states are formed in collisions with magnesium, while (4sσ) and (3dλ) O 2 + Rydberg states are formed after charge transfer with cesium. The product Rydberg ions predissociate and the kinetic energy release distributions are measured using translational spectroscopy. The spectra display vibrational peaks from which the vibrational constant is extracted. It is argued that this vibrational constant also applies to the O 2 2+ ground state. The results match calculations from Larsson et al. (J. Phys. B 23 (1990) 1175) on the O 2 2+ electronic ground state.