Scanning-tunneling-microscopy images:: A fully ab initio approach

A fully ab initio approach to scanning-tunneling-microscope (STM) images is presented, treating the sample and the tip as a single system. The approach combines density functional theory with the Kubo-Greenwood formalism for the conductivity. The STM images are calculated by taking into account atomic relaxations that occur on both the surface and the tip due to their mutual interactions. illustrative examples will be presented for the ease of a clean A1(110) surface and the same surface with a vacancy, showing that buckling relaxations occur that smooth the STM images, reducing the observable corrugation pf the surface.