Long-range oscillatory interactions and the stability of metals and alloys: stacking faults in HClP and FCC structures

Abstract

The calculation of stacking fault energies by the method given by Blandin et al. (1966) has been extended to cover the case where the long-range oscillatory interaction has the asymptotic form V(r)=V₀cos(2k_Fr+ phi )/(2k_Fr)³. The limitations on the values of phi compatible with stability have been determined. Values of V₀ and phi derived from liquid metal structural data have been used to calculate stacking fault energies and indicate stability in cases where phi =0 implies instability. The noble metals are not well explained by this method and it is shown that the dominant three-ion interaction completely overwhelms the above two-ion interaction and provides the necessary stability.