Determination of chemical specific atomic interaction with scanning tunneling microscope

Abstract

We present an experimental technique to comparatively determine the shape of tip-atom interaction potential and interaction strength of individual atoms on a surface using a scanning tunnelling microscope. From the atom manipulation signals, the tip-atom force vector angle is measured as a function of distance. Remarkably, the force angle is found to increase linearly with reducing tip-height for a small distance variation, which enables to deduce the shape of tip-atom interaction potential, and the lateral force required to move individual atoms on a surface. This technique will be useful to comparatively determine interaction strengths of molecules and biomolecular systems on surfaces. © 2011 American Institute of Physics.