Role of long-range interactions in the melting of metallic surfaces

Abstract

Ion-shadowing and -blocking studies of melted layers on the (110) surface of Pb reveal an increasing melt thickness with temperature, which follows first a logarithmic growth law ‖ln(Tm-T)‖, then asymptotically a power law (Tm-T)-r, with r=0.315±0.015. The logarithmic and power-law growth result from short-range and long-range atomic interactions, respectively. The correlation length within the melted phase is determined to be ξl=0.63 nm and for the Hamaker constant we find W=(0.40±0.05)×10-21 J.