Structure of the Cu{100}-c(2×2)N surface: A scanning-tunneling-microscopy study

Scanning-tunneling-microscopy studies of the Cu{100}-c(2\ifmmode\times\else\texttimes\fi{}2)N surface reveal that it is covered with square-shaped structures with sides 52\ifmmode\pm\else\textpm\fi{}4 \AA{} long, running parallel to the 〈100〉 directions. Within these structures it is possible to resolve a square-based lattice, with a lattice parameter of 4 \AA{} consistent with the c(2\ifmmode\times\else\texttimes\fi{}2) structure. We use a lattice-parameter-mismatch model based on the bulk-lattice constants of ${\mathrm{Cu}}_{3}$N to account for the regularity in shape and size of the square-shaped structures.