Title screen

Spatial distributions of a potential established inside a crystal by an externally applied potential are investigated theoretically in Pd and PdH. The calculations were performed in the framework of the linear-response approach with full inclusion of the electron band structure obtained within a self-consistent pseudopotential scheme. Analysis shows that in clean palladium the potential amplitude is maximal at the octahedral sites of the fcc lattice where the hydrogen ions predominantly reside. On the other hand the corresponding amplitude is significantly lower at the palladium ion positions. We observe drastic modifications in the screening properties in Pd upon hydrogen absorption. Nevertheless, the potential amplitude in PdH is also small at the Pd sites, whereas that at the H sites is significantly larger. However, in PdH the H ions are located at places where a local shallow minimum in the induced potential amplitude is observed. These results only slightly depend on the magnitude of the momentum transfer.