Local correlation during Ostwald ripening of two-dimensional islands on Ag(111)

Using two-dimensional Ag adatom islands on Ag(lll) as a model system, we st udy the importance of local correlations in diffusion-limited Ostwald ripen ing. For the coverages studied (0.08, 0.21, and 0.3 ML), we find that the r ipening can be surprisingly well described in a nearest neighbour model bas ed on pairwise atom exchange between neighbouring islands. The results reve al the local nature of diffusion-limited Ostwald ripening and demonstrate t he limits of the mean-field theories in describing experimental data. (C) 1 999 Elsevier Science B.V. All rights reserved.