Atomic-scale structure: From surfaces to nanomaterials

This brief overview is dedicated to Professor G. Ertl's profound influence on shaping the field of surface science. I sketch recent accomplishments toward the determination and understanding of the atomic-scale structure of nanostructures. I argue that, to properly understand nanoscience and develop nanotechnology, there is a dire need to determine many more than the ∼1,000 detailed surface structures known today. Techniques need to be adapted or invented to make this possible. As will be exhibited here, only two techniques are now essentially ready for this task: scanning tunneling microscopy, if interpreted by theory, and, to a lesser extent, x-ray diffraction. I also describe how low-energy electron diffraction is currently being developed for the same purpose.