Metastable ordered arrays of size-selected Ag clusters on graphite

We employ high-resolution transmission electron microscopy to explore the deposition of large size-selected Ag-N clusters (N=1100 to 5000 atoms) on the model graphite surface. We find that Ag-5000 clusters (only) form metastable, ordered arrays, nucleated at surface defects, which are stable for at least a day. The results suggest that the cluster coalescence is strongly dependent on cluster size, and that it should be possible to fabricate large-scale, two-dimensional, and metastable arrays of clusters in the size regime 5-10 nm. (C) 2003 American Institute of Physics.