Addimer diffusion on the Si(100) surface

Diffusion of silicon addimer along the trough and from the trough to the to p of dimer row on the Si(100) surface are investigated by tight-binding mol ecular dynamics calculations using the environment-dependent tight-binding silicon potential and by ab initio calculations using the Car-Parrinello me thod. The studies discover new diffusion pathways consisting of rotation of addimer. These new pathways have energy barriers in excellent agreement wi th experiment data and are more energetically favorable than other diffusio n pathways studied previously.