A novel heterogeneous system which consisted of a metal on a highly corrugated transition-metal oxide surface was examined by scanning tunnelling microscopy. The Pt formed 3-dimensional nanoclusters, with a narrow size distribution, on the anatase (001)-(1x4) surface. Upon annealing in a vacuum, the Pt clusters (which initially existed on

terraces) migrated to step edges, without coalescing, via a cluster diffusion mechanism. Time-dependent autocorrelation analyses revealed that the diffusion occurred preferentially along atomic rows. The diffusion barrier and pre-exponential factor along this direction were deduced to be about 0.27eV and about 400Å2/s, respectively.

Formation and Diffusion of Pt Nanoclusters on Highly Corrugated Anatase TiO2(001)-(1x4) Surface. S.Gan, A.El-Azab, Y.Liang: Surface Science, 2001, 479[1-3], L369-74