Ultra-Thin Films on Complex Metallic Alloy Surfaces: A Perspective

Complex metallic alloys (CMAs) may be defined as those intermetallic compounds having large (>~nm) unit cell dimensions. This includes quasi crystals as a special case, the unit cell being infinite. The discovery of quasi crystals motivated the study of CMAs, and the surface science community became active in the field once stable samples of sufficient size were produced. While the initial surface science activity centred on clean surface preparation, increasingly the formation of thin films, both metallic and molecular grew in importance. In this chapter, we give a brief introduction to this topic and then focus on several current areas of interest. These include the growth and characterization of ultra-thin metallic films of diverse architectures, the formation through deposition of novel molecular overlayers and thin films, complex intermetallics such as surface alloys and the potential use of intermetallic surfaces for catalytic reactions.