Predissociation rates of the A 1Π state of CH+

Abstract

Levels of the A 1Π1 state of CH+ which lie above the C+(2P1/2)+H(2S) dissociation limit may be predissociated by radial coupling with the a 3Π1 state and by rotational coupling with the X 1Σ+0 state. In addition, predissociation by tunneling may also occur for shape resonance levels above the C+(2P3/2) +H(2S) dissociation limit. The spin-orbit coupling matrix element has been derived as a function of internuclear distance. Predissociation widths, and hence lifetimes, for all levels have been calculated for both radial and rotational processes, as well as for the previously considered tunneling process. The calculations indicate that radial and rotational coupling are of major importance in determining the lifetimes of these levels, often dominating even for levels where tunneling is possible. Almost all of the levels between the two dissociation limits are, according to this calculation, significantly predissociated.