Structural determination of stable MoOx monolayers on O/Cu3Au(1 0 0): DFT calculations

Using ab initio calculations based on density functional theory (DFT), we propose a geometrical structure for MoO_x monolayers recently grown on O/Cu₃Au(1 0 0) substrates. The proposed structure reproduces the p(2 × 2) symmetry found by scanning tunneling microscopy (STM) and low-energy electron diffraction (LEED), as well as the intermediate oxidation state between Mo(IV) and Mo(VI) identified by X-ray photoelectron spectroscopy (XPS). Simulated STM images assign the bright spots in the experimental images to oxygen 2p states.