Rotational transfer in diatom–diatom collisions

We present a kinematic hard ellipsoid model of rotational transfer in diatom–diatom collisions. The model extends the principles of the angular momentum (AM) model of rotational transfer (RT) developed for atom–diatom collisions and the hard ellipsoid model of the repulsive potential. Monte Carlo trajectory calculations are performed on the Na2+H2 system which show excellent agreement with published experimental data, using only atomic masses and bond lengths as the input data.