Binding Site Transitions Across Strained Oxygenated and Hydroxylated Pt(111).

The effects of strain σ on the binding position preference of oxygen atoms and hydroxyl groups adsorbed on Pt(111) have been investigated using density functional theory. A transition between the bridge and FCC binding occurs under compressive strain of the O/Pt(111) surface. A significant reconstruction occurs under compressive strain of the OH/Pt(111) surface, and the surface OH groups preferentially occupy on-top (bridge) positions at highly compressive (less compressive/tensile) strains. Changes to magnetisation of the O- and OH-populated surfaces are discussed and for O/Pt(111) oxygenation reduces the surface magnetism via a delocalised mechanism. The origins of the surface magnetisation for both O- and OH-bearing systems are discussed in terms of the state-resolved electronic populations and of the surface charge density.