Scattering at surfaces

The nonthermal character of molecule/surface interaction becomes evident from the angular distribution of particles from a monochromatic molecular beam scattered at a surface, as reproduced in Fig. 3.1 for a Pd(l 11) surface [2]. 

FIGURE 3.2. Angular distributions of H2 and D2 molecular beams scattered from a Ni(l 10) surface [5]. 

The Lennard-Jones potential diagram reproduced in Fig. 1.4 illustrates the progress of dissociative adsorption only in a simplified one-dimensional manner. In reality, this process is 

FIGURE 3.3. Energetics of dissociative adsorption of a diatomic molecule, (a) Schematic cartoon, (b) One-dimensional Lennard-Jones potential, (c) Two-dimensional representation with contour hnes as a function of the distance X from the surface and the separation y between the two atoms. (See color insert.) 

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NIehus H, Helland W and Taglauer E 1993 Low-energy Ion scattering at surfaces Surf. Sc/. Rep. 17 213-304 An excellent review of ion scattering. 

Electron-atom scattering is central to all techniques under discussion here. As we have mentioned, electron-atom scattering at surfaces has been treated almost exclusively by means of the muffin-tin model. 

This qualitative account serves to underline the complexity of the physical processes involved in forming the ion image, and the difficulty of arriving at a detailed interpretation. Neither the theory of atom scattering at surfaces, nor the description of field ionization are sufficiently advanced to allow a quantitative account of image intensities. However, such a quantitative evaluation is not really necessary in... 

Losses due to wave scattering at surface obstructions such as gas inlet, microphone, and windows. 

Niehus H, Heiland W, and Taglauer E (1993) Low-energy ion scattering at surfaces. Surface Science Reports 17 213-303. 

NIE Niehus, H., Heiland, W., Taglauer, E. Low-energy ion scattering at surfaces Surf. Sci. 

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