Modeling inelasticity and failure in gold nanowires

We present numerical simulations of gold nanowires under tensile loading at various strain rates and wire sizes at room temperature. The simulations were performed using molecular dynamics modeling the gold nanowires using various forms of the embedded-atom method, and concentrated on investigating the yield and fracture properties of the nanowires. It is clearly demonstrated that the accurate modeling of stacking fault and surface energies is critical in capturing the fundamental deformation behavior of gold nanowires. By doing so, phenomena which have been observed both experimentally and numerically in first-principles calculations, such as the formation of atom-thick chains (ATCs) prior to fracture, zigzag, helical rotational motion of atoms within the ATCs, structural reorientation of the ATCs to a hexagonal crystal structure, and (111) faceting of the nanowire in the yielded neck region by the ATCs, are accurately captured.