The (1 x 4) reconstruction of the stoichiometric anatase TiO2(001) surface was studied via first principles density functional calculations. A new structural model was proposed for this reconstruction, which was energetically much more favourable than all the other available models, including the unreconstructed (1 x 1) surface. In this model, rows of TiO3 species periodically replace rows of surface bridging oxygen atoms of the (1 x 1) surface, thus leading to a relief of the large surface tensile stress present on that surface. The corresponding empty-state charge density distribution correctly describes the experimental scanning tunnelling microscopy images.

Stress-Driven Reconstruction of an Oxide Surface - the Anatase TiO2(001)-(1 x 4) Surface. M.Lazzeri, A.Selloni: Physical Review Letters, 2001, 87[26], 266105 (4pp)