Lattice dynamics and superconducting Tc for dilute H and D interstitials in Al

The lattice dynamics of isolated H and D interstitial ions in A1 have been calculated with the initial aim of establishing the local mode frequencies. Kohn-Sham nonlinear screening was used for the H,D potentials, anharmonic effects due to the large interstitial motion were accounted for within a quasiharmonic approximation, and the relaxations of the A1 neighbors of an interstitial were also included. The calculations were carried out for both …