Calculations on energy transfer to a diatomic molecule in high-energy head-on collisions

Abstract

In collisions where the incident particle has zero impact parameter with respect to one of the atoms of the molecule the energy transfer and the scattering angle are calculated as functions of energy and molecular orientation. The interaction between the atoms of the molecule and the incident particle is described by an exponential potential. Three intramolecular potentials are used: a harmonic, a Morse and a modified Buckingham potential. No important differences are found in the results of the application of the last two potentials. At low energies the energy-transfer data and (laboratory) small-angle scattering data show that the molecule, in its totality, is involved in the collision. When the energy is increased only one atom of the molecule is involved in the collision, while the other is “watching” the collision. These so-called “stripping” or “spectator” collisions reveal, as it were, the mass structure of the molecule. Finally some experimental data are discussed in connection with this collision model.