Semiclassical treatment of resonances in the collinear O + HO exchange reaction

Feshbach type sharp resonances appearing in the O+HO collinear reaction are analyzed by the newly completed semiclassical theory for the Landau-Zener-Stueckelberg type curve crossings. Not only the resonance positions but also the widths are nicely reproduced in comparison with the exact numerical calculations, even when the widths are as small as 10−8∼10−11 au. The semiclassical theory is extended so as to be applicable to the case that the bottom of the upper adiabatic potential is higher than the crossing point.