Stress and reconstruction on (001) transition-metal surfaces

摘要

We investigate the role of surface stress in the hex reconstruction of (001) transition-metal surfaces introducing the density-functional-theory stress density, a theoretical tool allowing the local analysis of the stress. By ab initio total energy, stress, and stress density calculations for Ir (001) we show that the reconstruction is due to the concurrence of tensile stress relief in the surface layer and the huge outward relaxation thereof. The latter causes a compressive stress relief in the region between the surface layer and the substrate, leading to an increased total surface stress.