A generalized description of time-dependent ion-atom collisions

During the last years we were able to describe electron transfer and excitation in many electron ion-atom collisions as a time-dependent process. As basis function we used relativistic molecular wave functions from static molecular calculations. This is correct for the adiabatic collisions, i.e. slow collisions. In case of high energetic ion-atom collisions the diabatic description would be much more appropriate. In this paper we describe a generalized ansatz by using explicit translational factors. This description not only changes the coupling matrix elements in the coupled channel calculations but allows an automatic adaption of the basis to the energy of the electrons in the collision. The inclusion of centre of mass centred basis functions in addition allows an interpretation of the saddle-point electrons emitted in such collisions.