Abstract Theoretical results on the electron dynamics and on resonant level broadening in slow atomic interactions with metal surfaces and thin metallic films are presented. Within the time-dependent close-coupling method, a wave-packet approach is introduced in which nondiagonal couplings in the subspace of metal states are taken into account. This approach is applied in a study of the time evolution of the occupation of hydrogen states in front of a semi-infinite metal. First-order level widths are calculated for hydrogenic atoms interacting with thin metallic films. They are found to exhibit pronounced size-quantization effects arising from the confinement of the electronic motion in the growth direction of the film.