An approach to the atomic structure of bulk metallic overlayers using tip-induced layer-by-layer dissolution

Well-grown 3-D copper clusters were obtained on a Pt(111) surface at interm ediate overpotentials from a sulfuric acid solution. The hexagonal and tria ngular clusters grew layer-by-layer and were aligned to the orientation of the substrate, indicating epitaxial growth without rotation. By using the t ip as an anodic electrode, the atomic structure of each layer of the cluste r was monitored locally during dissolution. The results show that in the co pper clusters the lattice constant relaxes directly to the bulk lattice con stant in the second layer (at least after deposition of the third layer). A dditional discussion on the dissolution kinetics is also included. The same method has been used to elucidate the structure of the Cu overlayer on Pt( 100). (C) 2001 Elsevier Science B.V. Ail rights reserved.