Influence of Adsorbate Monolayer on the Nano-Mechanics of TIP-Substrate Interactions

Abstract

ABSTRACTWe employ constant temperature molecular dynamics simulations to study, at the atomistic level, the interactions of an Ir tip with a Pb substrate. We have considered the complete cycle of approach.contact, indentation and retraction of the tip from the substrate. We have observed the wetting of the tip by the substrate atoms, and the formation of atomic necking between the tip and the substrate.We have carried out further simulations to study the interactions of an Ir tip with an Ir substrate covered with an adsorbate monolayer of Pb film. We show that the introduction of the adsorbate considerably reduces the work of adhesion and the extent of plastic flow, in agreement with experimental results.Three-dimensional geometries have been generated on computer and used for the animation of the simulation runs.