Predissociation by the continuum of a bound state without curve crossing. Application to the spectrum of OH

Abstract

Calculations of the Franck-Condon overlaps between the bound vibrational levels of the A²∑⁺ state of OH and the continuum levels of the ground state X²Π suggest that the weak predissociation of the levels ν= 2-5 could be due to a direct predissociation to the ground state and not to the crossing by another excited state. Accurate measurements of the intensity of the emission lines could test this hypothesis.