Computer simulation of Pb/Al interfaces

Abstract Monte Carlo simulation, in conjunction with glue-type empirical many-body potentials, has been used to model the structure of (111) and (100) Pb/Al interfaces as well as calculate their interfacial free energy. Vibrational contributions to the free energy were accounted for within the framework of the local harmonic approximation, and configurational free energy was described on the basis of a point approximation for the entropy of mixing. The calculated free energy ratios for the Pb/Al {100} and {111} interfaces are in good agreement with recent high resolution transmission electron microscopy measurements performed in the range 500 K K . The simulations indicate a strong temperature dependence of the free energy ratios, from 1.10 at T=500 K to 1.31 at T=0 K . Comparison of the present results with previous calculations of the anisotropy of surface energy of pure Pb shows that the glue potential correctly reflects the large change in anisotropy which is observed experimentally between isolated Pb crystals and Pb crystals embedded in Al.