Mixed dissociated/molecular monolayer of water on the TiO2(0 1 1)-(2 × 1) surface

A combined theoretical and experimental approach is used to study water on the TiO2(0 1 1)-(2 × 1) surface. Based on simple proximity arguments dissociative adsorption is expected. Density functional theory and photoemission spectroscopy show that, at low temperatures, a mixed molecular/dissociated water monolayer is stabilized by a H-bonding network. Scanning tunneling microscopy and molecular dynamics simulations provide evidence of a dissociated layer with a preferential non-uniform arrangement of the adsorbates at room temperature.