Syllabus
* Electronic and geometric structure of surfaces
Basic ideas of theoretical description, surface geometry, principles, possibilities and limits of LEED technique, examples of reconstruction and relaxation of semiconductor and metal surfaces. From simple models to first principles calculations of electron structure, surface states, bands, redistribution of charge. Basic concepts, advantages and disadvantages of various approaches for solution of motion equations.
* Adsorption of individual atoms
Chemisorption on metal surface, hybridization of states, comparison of classical ideas with results of calculation for various types of atoms, energy balance, ab initio calculations of energy barriers for elementary diffusion processes.
* Adsorption of molecules
CO molecule on transition metal surface, classical ideas (HOMO, LUMO) and results of calculations based on density functional approximation (DFA). Basic ideas for description of co-adsorption, chemical reactions on metal surface. Example: dissociation of a simple molecule on metal surface.
* Layer of atoms adsorbed on surface
Work function, ionization and screening, surface band structure, photoemission intensity profiles - densities of states, calculation of intensity, electron structure mapping, photoemission in ultraviolet and X-ray bands, examples
* STM
Why is the interpretation of STM images difficult? What can be seen in STM? Standard schema for interpretation: Tersoff - Hamann and Bardeen approximations, transport formulation of tunneling process. STM at semiconductor and metal surfaces - clean and covered by adsorbate. Theoretical calculation and experiment. Examples.
Annotation
Electron and geometrical structure of surfaces, adsorption of single atoms, adsorption of molecules, layer of atoms adsorbed on surface, interpretation of STM images.
The lecture is for specialists on solid state surfaces (experimentalists, technologists and theoreticians). Knowledge of quantum physics and solid state in a span of graduate study at the faculty together with basic surface science knowledge (crystallography and topography of surfaces, principles of experimental methods) are supposed.