Bonding of Gold Nanoclusters to Oxygen Vacancies on Rutile TiO₂(110)

Through an interplay between scanning tunneling microscopy (STM) and density functional theory (DFT) calculations, we show that bridging oxygen vacancies are the active nucleation sites for Auclusters on the rutile TiO₂(110) surface.We find that a direct correlation exists between a decrease indensity of vacancies and the amount of Au deposited. From the DFT calculations we find that the oxygenvacancy is indeed the strongest Au binding site.We show both experimentally and theoretically that asingle oxygen vacancy can bind 3 Au atoms on average. In view of the presented results, a new growthmodel for the TiO₂(110) system involving vacancy-cluster complex diffusion is presented.