Tailoring periodic nanostructures of vicinal copper surfaces: Formation and evolution of oxygen-induced faceting on Cu(3 3 2)

We report and model calculations of nanostripes formation of the Cu(3 3 2) surface obtained by oxygen-induced reconstruction. Scanning tunnelling microscope (STM) results with atomic resolution reveal alternate facets of clean Cu(1 1 1) and Cu(1 1 0)-O(2x1) along the [-1 1 0] direction, with the same average direction of Cu(3 3 2). At the edge between the two facets, oxygen is absorbed in a pseudo threefold site of the unreconstructed Cu(3 3 2). Tuneable periodicity, from 3 to 10 nm, is obtained by controlled change of the surface treatment. We discuss the formation of the periodic nanostructures and the mechanism driving the reconstruction via model calculations.