Density functional study of Aun (n = 3-5) clusters on relaxed graphite surfaces

Energetics and configurations of gold clusters Aun (n = 3-5) on graphite surfaces were investigated using a density functional approach with atomic-type orbitals and relativistic core pseudopotentials. The gold trimer adopted a range of binding configurations including both triangular and linear cluster geometries and both perpendicular and parallel orientations to the surface. Tetramers preferentially adopted the vertical surface orientation in a rhomboid geometry, while pentamers tended to lie parallel to the surface in structures slightly distorted from the planar geometry of the isolated cluster.