Abstract
Vibrationally induced autoionization and one class of predissociation of electronically excited and its isotopes are treated by a perturbed-stationary-state theory. Autoionization and predissociation rates are given for a number of states of , HD, and . In addition to direct bound-continuum coupling, consideration is given to effects of higher-order coupling; these effects cause order-of-magnitude changes in isolated cases. The auto-ionization rates vary with principal quantum number as , directly with vibrational energy , and decrease sharply with vibrational quantum change . As the principal quantum number increases, transitions of successively smaller become possible; the net effect of this is to override the dependence in total autoionization rates. Competition between predissociation and autoionization is examined; the two processes show very different dependence on and , with the consequence that decay in most regions of () space is dominated by one or the other process; but the two mechanisms are competitive for some () states. The isotope effect also is rather different for the two decay processes, enough so that, in effect, the isotope effect amounts to a qualitative change from one mechanism of decay to the other, with mass change.
- Received 4 August 1969
DOI:https://doi.org/10.1103/PhysRevA.1.395
©1970 American Physical Society