The interaction of deposited gold adatoms and dimers with multilayer relaxed graphite surfaces is investigated through a density functional approach with numerical orbitals and a relativistic core pseudopotential. The energy landscape for a gold adatom along ͓110͔ agrees with scanning tunneling microscopy observations including the preferred ␤ binding site for adatoms and the mobility difference between silver and gold adatoms. Deposited particles are shown to induce surface deformation and polarization. Static relaxation and dynamic simulations indicate that the energetically preferred binding orientation for a gold dimer is normal rather than parallel to the graphite surface. The dimer response to a simulated scanning tunneling microscopy tip is investigated by molecular dynamics simulations.

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A many-body potential for strontium clusters is developed with parameters fitted to the energy surface of strontium clusters containing up to ten atoms calculated within the density functional theory in the generalized gradient approximation. Structure and energetics of the most stable cluster isomers with up to 63 atoms are obtained with genetic algorithms. Additionally, the high resolution mass spectrum of strontium clusters up to Sr 96 at finite temperature is provided. Several thermodynamic properties are studied under the many-body potential as a function of temperature. It is found that stability patterns, indicating how stable a cluster size is with respect to its neighboring sizes, change significantly with temperature. This behavior is due to structural transitions of the strontium clusters that occur at finite temperatures. A comparison with the experimental mass abundance indicates that only the structures above 400 K were observed experimentally. Very prominent magic numbers are predicted at 34 and 61.