SEMICLASSICAL ANALYSIS OF RESONANCE STATES INDUCED BY A CONICAL INTERSECTION

The resonance states induced by nonadiabatic coupling in the conical i ntersection problem are analyzed semiclassically. Not only the general framework but also the explicit analytical expressions of resonance p ositions and widths are presented. Interestingly, the nonadiabatic tra nsition schemes are found to be quite different in the two representat ions employed, i.e., the adiabatic and generalized adiabatic (or dynam ical state, or postadiabatic) representations. In the former case the transition is assigned to be of the Landau-Zener (LZ) type, and the la tter case is analyzed by a mixture of LZ- and Rosen-Zener (RZ)-type in the case of m greater than or equal to 3/2 and by the nonadiabatic tu nneling (NT) type in the case of m=1/2, where m is the angular momentu m quantum number. Both of these semiclassical results agree well not o nly with each other in spite of the very different schemes, but also w ith the exact numerical results in a wide range of energy and angular momentum. (C) 1996 American Institute of Physics.