Momentum transfer and total scattering cross sections for ions with polar molecules

The scattering of ions by polar molecules has been studied using numerical techniques. Because of the long range potential of interaction the scattering cross sections are very large. The total scattering cross section and rotational energy transfer cross section are of the order of thousands of Ų for the cases studied. The momentum transfer cross sections are 1.3 to 2.0 times the capture cross sections in contrast to the ${\sigma }_m{\mathrm{/\sigma }}_c\text{=1.105}$ for Langevin collisions. However, the scattered intensity $\mathrm{I(\theta )}$ at impact parameters less than 20Šcan be quite anisotropic because of the nature of single reflection collisions.