Non-adiabatic transitions between two groups of interesting energy levels

Abstract

The problem of non-adiabatic transitions between two groups of pseudocrossing potential energy curves is formulated in terms of two interacting quasistationary states. The method developed is applied to the multiple curve-crossing problems appearing in the A^-+BC⁺( nu ) to A+BC( nu ') and A*(n)+A to A*(n')+A reactions. Closed-form expressions for the transition probabilities between two given states are derived, with account being taken of the effect of other states under realistic assumptions for the curve-crossing parameters.