DFT study of oxygen adsorption on W(112) surface

Oxygen adsorption on the W(1 1 2) surface has been simulated within DFT in local density approximation. It has been found that at 1 ML coverage, quasi threefold hollow sites, coordinated by two W atoms of the row and one W atom of the next layer, are favored for oxygen atoms. In contrast to the structures of oxygen on the Mo(1 1 2), p(1 x 1) oxygen structure on the W(1 1 2) surface at the one monolayer coverage is predicted. At a half monolayer coverage, preferred sites for oxygen adsorption are found to be the bridge-on-row sites, similarly to results for the p(2 x 1) oxygen structure on the Mo(1 1 2) surface, reported in recent VASP simulations. The stability of the W(1 1 2) surface under oxygen adsorption is discussed as well. The surface relaxation is accompanied by the redistribution of density of states, associated with transformations of surface states. (C) 2005 Elsevier B.V. All rights reserved.