Multiscale modeling of supported metal clusters: Exploring the electronic structure of nano-catalysts

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Mono-disperse model catalysts produced by soft-landing of small mass-selected transition metal clusters (e.g. PdN or PtN) on metal-oxide surfaces (Mg0, Ti02, Al203 etc.) represent systems which are especially suitable for a comparison with theoretical calculations of catalytic reactions on clusters (e.g. CO oxidation or NO-CO reaction). Numerical studies in the framework of spin density functional theory have shown that small supported Palladium clusters exhibit finite magnetic moments. The proposed project aims to study the influence of cluster spin on the dynamics and outcome of cluster-catalyzed reactions. Employing the Born-Oppenheimer Local-Spin-Density Molecular Dynamics method, the spin-dependence of reaction barriers, the energetics of the adsorption sites of the reactants and probabilities of reaction pathways will be explored for important environmental processes, namely the CO oxidation and the CO-NO reaction on supported Pd and Pt clusters. In analogy to the so-called "structural fluctionality" where cluster structural deformation initiates a catalytic reaction, cluster spin flips might lead to the lowering of reaction barriers. The main goal of this study consists in the exploration of such a "spin-fluctionality".