Vacancy Diffusion in an Adsorbed Layer

Bromine dissociatively adsorbs on Cu(100) to form a c(2x2) layer of chemisorbed bromine atoms. In the c(2x2) structure, every other hollow in the Cu(100) surface is occupied by a bromine atom. The periodic features in each frame are due to this structure. In the movie several vacancies diffuse through the scan window. Each image was acquired in 2.5 sec.