In order to establish the jump processes which were important in diffusion on a 2-dimensional surface, the movement of individual Pd atoms on W(110) was examined. From the distribution of Pd displacements at high temperatures, double jumps along the close-packed <111> directions were identified. For the first time, large differences were observed between the mean-square displacements along x and y; thus demonstrating the existence of unexpected contributions from jumps along <110>, but not along <001>. These jumps occurred over activation barriers that were higher than those for single jumps.

Non Nearest-Neighbour Jumps in 2D Diffusion - Pd on W(110). S.M.Oh, S.J.Koh, K.Kyuno, G.Ehrlich: Physical Review Letters, 2002, 88[23], 236102 (4pp)

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