Size-Selected Clusters on Oxide Surfaces

Binding and activation of molecular O2 by the model catalyst are necessary elementary steps in the CO oxidation process [65, 66], and thus understanding the 

Impurity-doping Effects Finally, we address the possibility of enhancing the 

Analyzing the products formed on small size-selected Pd (1 n 30) clusters deposited on MgO(lOO) thin films indicates that the surface intermediate C4H4 is produced efficiently on all cluster sizes. Thus at least two acetylene molecules are adsorbed in a ti-bonded configuration at the initial stage of the reaction [71]. The observed size-dependent selectivity may then be understood by regarding the influence of the cluster size to steer the reaction either towards the cyclotrimerization to form or towards a direct hydrogen transfer from adsorbed C2H2 to the 

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FTIR has been successfully applied for studying chemical properties of size-selected clusters on oxide surfaces [39,192,244,252]. In these experiments, the clusters were deposited onto thin oxide films grown on a metal single crystal. In this approach, the metal is used as the mirror in the optical setup the oxide films ought to be thinner than the wavelength of the IR radiation. In this way, vibrations of adsorbates on size-selected clusters with densities as low as 0.2% ML could be detected. Mechanistic information of chemical reactions... 

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