It was recalled that the clean (100) surface reconstructed so as to form a pseudo-hexagonal (5 x 27) outermost layer. This structure was observed both under ultra-high vacuum, and in electrochemical environments at potentials which corresponded to small negative surface electronic charges. By using an ultra-high vacuum scanning tunnelling microscope at 77K, it was observed that the reconstruction could be lifted by high positive sample biases. A 20% less-dense bulk-terminated surface was produced, and the excess material appeared as irregularly shaped Au clusters. However, over a period of a few minutes, the surface relaxed back to the pseudo-hexagonal phase. This process could also be monitored by means of scanning tunnelling microscopy.

J.Buisset, H.P.Rust, E.K.Schweizer, L.Cramer, A.M.Bradshaw: Journal of Vacuum Science and Technology B, 1996, 14[2], 1117-20