Motion of in-channel dimers on W(112): A DFT study

The adsorption and the mechanism of motion for in-channel tungsten dimers on a W(112) surface were investigated using DFT ab-initio calculations. The dimers turn out to diffuse as one object with an activation energy of 1.2 eV, and motion is accompanied by a response of the lattice. Additionally, we explored the dimer dissociation–association process and the length of adatom–adatom interactions. It was also found that the long-range interaction between tugsten adatoms in the same surface channel influences the height and shape of the activation barrier for the diffusion of adatoms.