Surface Stress of Metallic Nanoparticles Revisited

Abstract

The surface energy has been one of the topics of atomistic research for nanoparticles in the last decades. However, the physical role of surface stress and its quantification have been a lot less an object of research. Assumptions for the surface stress, going back to the thermodynamic basis of continua, have been popular. As an example the surface stress (state) follows as derivatives of the surface energy with a rather "classical" evolution equation for the deformation energy. The current concept introduces a combination of atomistic modelling and continuum mechanics for a core-shell system. Considering crystalline gold nanoparticles with radii in the range of 1nm to 9 nm, a unique equation can be derived for the surface stress.

Keywords: Nanoparticles, Atomistic modelling, Deformation, Shape dependence, Surface energy, Surface stress