A new dual-target dual-laser vaporization source for the production of binary metallic clusters is presented. Clusters of the type AunXm (X=Al, Fe, Co, Ni) were produced. Excellent control over the mixing process was achieved by varying the delay time between the firing of the two lasers and their energy densities. Having identified these critical parameters, their influence over the production process is shown in detail for the AunAlm system. The production of bimetallic clusters in this source is due to the spatial and temporal overlap of the two laser vaporized materials in the source.

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We investigated the cluster-surface interaction of Au clusters deposited on MgO cubes and on amorphous carbon, and its influence on the morphology of the Au cluster. Au clusters, produced in a laser vaporization source, are deposited with low energy on carbon-coated microscope grids on which MgO cubes are first deposited as substrates. Clusters on the amorphous carbon as well as clusters on the MgO cubes are studied by high-resolution electron microscopy ͑HREM͒. The clusters have different morphologies for the two different surfaces, and a dilation of the Au lattice is also measured for the clusters deposited on the crystalline surface of MgO to perfectly accommodate the MgO lattice. Classical molecular dynamics ͑MD͒ is applied to model this behavior. Good agreement is found between experimental cross-section HREM images and theoretical images simulated with the multislice technique using the model calculated by MD.

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