Adsorption and growth on metal surfaces studied on the atomic scale

START project Y 75 Adsorption an growth on metal surfaces on the atomic scale Michael SCHMID 20.06.1997 For the ultimate goal of designing new materials for catalysis and high-density magnetic data storage it is necessary to understand the basic processes involved on the atomic scale. It is the aim of this START project to gain more insight into the atomic-scale phenomena relevant by surface science techniques, mainly scanning tunneling microscopy at low temperatures, which should yield a real-space atom-by-atom view of the structures and fundamental processes slowed down or frozen in. Due to the widespread use of platinum alloys in catalysis, studies of gas adsorption are planned mainly on Pt alloy surfaces, where the difference between adsorption at the elements making up the alloy surface gives rise to phenomena not found on pure metal surfaces. Adsorption studies on pure elements should focus on "hot topics" in fundamental research, such as the possibility of transient mobility, i.e., the conversion of adsorption energy to kinetic energy sufficient for migration over large distances. The work on ultrathin magnetic films should focus on atomically resolved studies of the growth and structure of these films. Besides resolving open questions on the intensively studied system Fe/Cu(100), it is planned to study the processes leading to a more ideal layerby-layer growth when surfactants are added. Since magnetic storage devices are based on magnetic alloys, much emphasis should be on the growth and structure of ultrathin alloy films, mainly PtCo alloys, which are not only interesting from the viewpoint of fundamental research but also a promising candidate for future high-density recording. Influence of the proposed work on the development of the field The research programme should add an atomic-scale view to the space-averaging techniques or studies with lower resolution of many effects, structures and phenomena. This will not only provide a more detailed description of phenomena already known, but it should also show new effects and phenomena overlooked or inaccessible to other studies and allow to resolve open questions. Based on the own experience on alloys, it is estimated that the research will bring especially the fields of adsorption on and growth of alloys a great deal further. Although the work will be in basic research, it is expected to narrow the gap between fundamental studies and application. Many of the systems studied will be closer to "real" or industrial systems than much of today`s basic research in surface science, such as the work on alloys in contrast to pure metals much more common in surface science.