Atomic diffusion on nanostructured surfaces

The behaviour of a set of cobalt adatoms on the herringbone reconstruction of gold has been investigated through a combination of classical molecular dynamics and the nudged elastic band method. A strong diffusion anisotropy is evidenced on the fee and hcp parts of the reconstruction. It favours the diffusion of the cobalt adatoms toward the discommensuration lines. Then, the discommensuration lines act as diffusion channels for the cobalt adatoms movement, by focusing them to the kinks of the reconstruction, where the cobalt clusters nucleation takes place. (C) 2008 Elsevier Ltd. All rights reserved.