| 24.01.2008 |
Get real! Describing and understanding the properties and functions of materials from first principles
Prof. Dr. Matthias Scheffler, Fritz-Haber-Institut der MPG, Berlin |
It has been known since long that materials are built from atomic nuclei and electrons, and that their functions come to light only over time scales of milliseconds or longer. For example, metals corrode with just one atomic layer per minute. Nevertheless a reliable modeling of material properties and functions that is based on quantum mechanics and covers time spans of minutes became possible only recently. Electronic structure theory (the nature of the chemical bond) is the basis and the finest scale for multi-scale modeling of the function of materials. It must be the basis. Frequently it is assumed that details at this basis do not matter when length and time scales approach meso- or macroscopic proportions (e.g. mm and seconds). In this talk I will show for various examples that details matter indeed. When the accuracy is lacking at the base, there is little hope for predictive results at any level of modeling that follows. This talk describes the basic concepts involved in this bridging of time and length scales from electronic to macroscopic. For example, the so-called materials-gap and pressure-gap challenges of surface science and real-life catalysis are handled as well. Specifically, I will discuss examples from (1) growth of semiconductors, metals, and surface oxides, (2) heterogeneous catalysis and (3) surface chemical reactions. Focusing on physical phenomena and new understanding, the talk will also give an impression about the methodology, which has been developed in recent years, and the type of problems that can now be tackled with this new methodology and the availability of high-performance computers.
Einladender: Prof. Dr. J. Pollmann
| Ort: |
Wilhelm-Klemm-Str. 10, IG I, HS 2 |
| Zeit: |
donnerstags 16 Uhr c.t. |
|
Kolloquiums-Kaffee ab 15:45 Uhr vor dem Hörsaal |
Im Auftrag der Hochschullehrer des Fachbereichs Physik
Prof. Dr. J. Pollmann
