Adsorption of glycine on Cu(001) and related step faceting and bunching

Adsorption of glycine on the Cu(001) surface has been studied with scanning tunneling microscopy. In addition to confirming the Cu(001)c(2 x 4)-glycin e to be the major superstructure on the surface, it has been found that on the surface all steps are faceted to [310] directions and that the faceted steps may bunch together to form Cu{3 1 17}1 x 1-glycine facets. On the bas is of our STM images and the local structure of glycine adsorbed on Cu(110) reported recently, models have been proposed for the Cu(001)c(2 x 4)- and Cu(3 1 17)1 x 1-glycine superstructures for further investigation. The mode ls explain quite naturally the motivations behind the step faceting and bun ching prosesses. (C) 1999 Published by Elsevier Science B.V. All rights res erved.