The Structure of Ideal Surfaces

The structure of real surfaces differs from the structure of ideal surfaces by the surface roughness. Whereas an ideal surface is atomically smooth, a real surface has defects, steps, kinks, vacancies, and clusters of adatoms (Fig. 3.16). 

A more detailed discussion of the structure of ideal surfaces and many other diagrams of surfaces can be found in [2.2],... 

The Physics of Solid Surfaces I 2.1 The Structure of Ideal Surfaces 981... 

Although, the view about the energetic heterogeneity of oxide surfaces is now commonly accepted, the nature of that phenomenon and its role in adsorption is not well understood yet. The structure of oxide surfaces is still often assumed to be corresponding to their ideal crystallographic structure. 

In general, the deviation from the ideal shape can be distinguished in three distinct areas in which the structure of a surface is cmistructed, namely ... 

Apart from the simulation of ideal surfaces, increasing interest in real 2-D crystals now exists, which are quasi-periodic structures in two dimensions but only a few atomic layers thick, and which may present new and useful properties precisely because of their limited thickness. This branch of nanoscience is then an ideal ground for application of the slab model. 

The porosity and permeability depend solely on the structure of the medium. In principle, if the entire geometry of the solid surface were known, these properties could be calculated by local volume-averaging [1]. As mentioned previously, this is not the case, except possibly for certain idealized situations. Arguably, there should... 

Krypton Sorption. Volumetric adsorption using gases with low saturated vapor pressure has been found to be an effective technique to gain detailed structural information for small quantities of porous materials, especially using krypton (Kr).27 The substitution of nitrogen by Kr reduces significantly the amount of unadsorbed molecules in the dead volume, allows for the characterization of small surface areas, and is thus ideal for mesoporous... 

---