| Abstract
| - The stability and structure of several palladium aggregates deposited onto the undefective MgO(001) surfacehave been studied by classical molecular dynamics, MD, simulations at different temperatures. The MDsimulations involve the simultaneous displacements of the ∼1800 atoms used to simulate the substrate andthe supported metal cluster. Pair potentials describing both the metal−metal and the metal−surface interactionshave been derived from density functional theory embedded cluster model calculations. Two different initialscenarios have been designed so as to investigate the growth pattern of the metal onto the oxide. For thedeposition of a 3D aggregate at different temperatures, the 3D character is retained but the initial shape isstrongly modified, leading to a cluster with a truncated octahedron shape limited by low-index, low-energyfaces, in accordance with experiment. A second limiting case is obtained when the initial configuration is ametallic monolayer arrangement. In this case, the monolayer structure is preserved at low temperatures andshort simulation times, indicating that, far from the equilibrium conditions, formation of monolayers cannotbe discarded, while at higher temperatures palladium deposit evolves to form 3D structures.
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