Catherine Lenihan

Molecular Dynamic Simulation of a Metal Crystal under Stress

We present a Molecular Dynamics study of stresses generated in a metal film (aluminum and copper) on a substrate. It is shown that the surface has limited influence on intrinsic stresses beyond a few atoms distance. Surface relaxation at an open surface was found to be consistent with accepted values for copper but the anomalous outward relaxation of the surface layers reported in some studies of aluminum was not recovered. Instead the surface layer relaxed inwards. The atomic structure surrounding a single vacancy in a crystal at temperatures from 100 to 300 K was also studied. A vacancy was found to occupy a volume less than an atomic volume; the contraction was just 0.95, which is considerably less than the previously‐predicted values.