Dynamic Processes on Solid Surfaces

When we see a jumbo jet at the airport, we sometimes wonder how such a huge, heavy plane can fly high in the sky. To the extent that we think in a static way, it is certainly not understandable. In such a manner, dynamics yields behavior quite different from statics. When we want to prepare an iron nitride, for example, one of the most orthodox ways is to put iron in a nitrogen atmosphere under pressures higher than the dissociation pressure of the iron nitride at temperatures sufficiently high to let the nitrogen penetrate into the bulk iron. This is the way thermodynamics tells us to proceed, which requires an elaborate, expensive high-pressure apparatus, sophisticated techniques, and great efforts. However, if we flow ammonia over the iron, even under low pressures, we can easily prepare the nitride-provided the hydrogen pressure is sufficiently low. Since the nitrogen desorption rate is the determining step of the ammonia decomposition on the iron surface, the virtual pressure of nitrogen at the surface can reach an extremely high level (as is generally accepted) because, in such a dynamic system, the driving force of the ammonia decomposition reaction pushes the nitrogen into the bulk iron to form the nitride. Thus, dynamics is an approach considerably different from statics.

Contenu

1. Theory of Atomic and Electronic Structure of Surfaces.- 2. Theory of Dynamical Processes of Surfaces.- 3. Real-Time Monitoring of Surface Processes by a Novel Form of Low-Energy Ion Scattering.- 4. In-Situ Observation Of Surface Processes By High-Resolution UHV Electron Microscopy.- 5. Catalysis by Structurally Designed Surfaces.- 6. Surface Compounds Formed on Single Crystal Metal Surfaces During Catalysis.- 7. Surface-Supported Metal Clusters: Molecular Approaches to Heterogeneous Catalysis in CO Hydrogenation.- 8. Laser-Induced Surface Reactions.- 9. IR Spectroscopic Studies on Surface Reactions.- 10. Catalysis by Heteropoly Compounds in the Pseudoliquid Phase.- 11. Surface Reactions Controlled by the Bulk Migration of Oxide Ions: Working Mechanism of Multicomponent Bismuth Molybdate and Scheelite-Type Oxide Catalysts.- 12. Chirality Recognition by a Clay Surface Modified with an Optically Active Metal Chelate.