Mesoscopic motion of atomic ions in magnetic fields

We introduce a semiclassical model for highly excited atomic ions moving in a magnetic field, which allows us to describe the mixing of the Landau orbitals of the center of mass in terms of the electronic excitation and magnetic field. The extent of quantum energy flow in the ion is investigated and a crossover from localization to delocalization with increasing center of mass energy is detected. Our model of the moving ion in a magnetic field turns out to be closely connected to models for transport in disordered finite-size wires.