A review of some selected two electron processes in ion-atom collisions

A brief review is given of some selected theoretical results obtained recently involving two electron processes in ion-atom collisions. We discuss: the removal of the Paul discrepancy; the improvement in the description of double ionization of helium; the difficulties being met by theoretical attempts to describe two-electron charge transfer; a classification scheme for correlated calculations and finally the reproduction of the experimental observation of the excitation of a one-electron helium ion in collision with a hydrogen atom. (orig.)