Molecular dynamics simulations of the liquid/vacuum surfaces of the room temperature ionic liquids [bmim][PF(6)], [bmim][BF(4)] and [bmim][Cl] have been carried out at various temperatures. The surfaces are structured with a top monolayer containing oriented cations and anions. The butyl side chains tend to face the vacuum and the methyl side chains the liquid. However, as the butyl chains are not densely packed, both anions and rings are visible from the vacuum phase. The effects of temperature and the anion on the degree of cation orientation is small, but the potential drop from the vacuum to the interior of the liquid is greater for liquids with smaller anions. We compare the simulation results with a range of experimental observations and suggest that neutron reflection from samples with protiated butyl groups would be a sensitive probe of the structure.

The properties of palladium clusters, generated with the electrochemical scanning tunneling microscope, have been investigated both by experiments and by computer simulations. The clusters are found to be larger and more stable if the tip is moved further towards the electrode surface in the generation process. The simulations suggest that the larger clusters consist of a palladium–gold mixture, which is more stable than pure palladium. Dissolution of the clusters occurs from the edges rather than layer by layer.

The structure and stability of palladium adlayers on Au(hkl) and Pt(hkl) were studied at different coverage degrees by means of Monte Carlo simulations using the interatomic potentials of the embedded atom model. In all cases the Pd films were found to grow epitaxially and pseudomorphically with the crystallographic orientation of the substrate. The differences and similarities of the adlayer with the substrate were analyzed.

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