Densities of interstitial electrons in Pd(Ni)-noble metal alloys

The ion core radii rc and interstitial electron densities nint for Pd, Ni, Ag, and Cu and for binary random alloys of these metals throughout the concentration ranges have been calculated on the basis of positron annihilation data. The differences in rc and nint for pure metals are suggested to be the main reason of different electronic structure of Pd-Cu and Pd(Ni)-Ag(Cu) alloys being the representatives of VCA and split-band alloys, respectively. (author)