Equation of state of ultra-narrow metallic nanowires

Equilibrium configurations of aluminum and nickel ordered nanowires are studied by means of a conjugate gradients minimization of the cohesive energy. The cohesive energy is computed using embedded atom method (EAM) semi-empirical potentials under two different parameterizations, in order to identify the influence of these approximations on the obtained results. We have tested, for several nanowire families, the concept of the nanowire equation of state which describes the nanowire cohesive energy as a function of its effective radius (reflecting the changes in the cohesive energy due to the presence of surfaces and edges). Using the equation of state we are able to determine the edge energies for different edge geometries. Our results show remarkable differences for these edge energies between both EAM approaches, as expected in low atomic coordination systems.