Precessional motion of asymmetric top complexes in reactive scattering

Differential reaction cross sections have been calculated from the classical precessional motion of a bent triatomic long-lived complex which constitutes an asymmetric top. The angular distributions are similar to those predicted by the Halpern Strutinski model for precession of a symmetric top but the singularities of this model are rounded off and the abrupt fall to zero is replaced by a smooth decline. Consideration of the stability of asymmetric top precession suggests that vibrational-rotational energy exchange may separate the motion of short-lived complexes rotating close to the plane of collision from the motion of those rotating far from the plane of collision.