Charge transfer in the Rydberg hydrogen atom metal surface interaction: a transition state approach

We study the classical dynamics of a hydrogen atom near a metallic surface in the presence of a uniform electric field. By continuation of families of periodic orbits and surfaces of section we show that, due to the electric field, the atom falls into a Stark regime through two pitchfork bifurcations. The charge transfer is studied by using the Dynamical Transition State Theory. Indeed, we obtain analytically the geometrical structures that in phase space regulate the ionisation of the atom and we calculate efficiently the ionisation probability as a function of the electric field strength.