Autoionization in diatomic molecules: An example of electrostatic autoionization in CO

Abstract

A review is presented of the different types of autoionization which have been studied theoretically in diatomic molecules: electronic (or electrostatic), rotational, spin-orbit and vibrational autoionizations. An example involving a large number of vibrational channels, is treated. It concerns the electrostatic autoionization in the 730–708 A wave-length region which appears in the CO photoionization spectrum. The structure observed at 721 A is explained by the enhancement in intensity of numerous levels of Rydberg series converging to excited vibrational levels of theA2II state caused by two autoionized Rydberg levels with aB2Σ+ core.