Spacehyphen;fixed vs bodyhyphen;fixed axes in atomhyphen;diatomic molecule scattering. Sudden approximations

摘要

The Arthurs and Dalgarno spacehyphen;fixed (SF) axes formulation of the quantum theory of atomhyphen;diatom scattering is compared with the bodyhyphen;fixed (BF) axes formulation of Curtiss using consistent notation to facilitate the comparison. While equivalent, the two theories are not always equally convenient. When rotation is treated in a sudden approximation, the BF formulation has a tremendous conceptual and computational advantage: It allows an infinitehyphen;order sudden approximation, independent of the form of the potential energy, which should be very helpful in vibrationally inelastic and reactive scattering problems. Also, a rapid procedure for calculating WKB phase shifts is presented.