**Author details**

It is thought that rapid progress of the nanostructures physics and ultra-high vacuum technology allow to obtain in near future single-crystal films only a few hundred Angstroms thick with clean entrance and exit surfaces and well-ordered adsorbate structure on them. It was shown that the magnitude of main maximum at *θ* ≈ *θ* lim depends on the height *h* of the adatom above the crystal surface. For the case Ne+ → Ni(100) + O, where film thickness (Δ*z* = 100 Å) and *E* <sup>0</sup> = 1 keV, maximum occurs at *h* = 0.9 Å, which is in agreement with the experi‐ mental value [57]. The sensitivity of the angular distributions of transmitted ions to shadowed adatom positions which do not correspond to the channel center in the given direction can be revealed by varying the direction of particle channeling. The accuracy with which the adatom adsorption site with respect to the unit cell in the transverse plane of the channel can be determined is evaluated as ~0.1 Å. An experimental test of this technique would permit a

One can draw the following conclusions on the basis of the conducted researches:

**•** A considerable influence of the binding of surface atoms to each other on the process of ion scattering in the low-energy range by polycrystal targets is experimentally established.

**•** The elastic energy losses are considerably smaller than the inelastic ones in a region of glancing ion scattering. The predominance of the inelastic energy losses should reveal itself in the efficiency of the various inelastic processes accompanying the glancing ion scattering

**•** From the comparison of the results of computer simulation of the scattered particle trajec‐ tories with the experimental energy distributions, one can draw a conclusion that for bombardment of a Cu(100) surface with *E* 0 = 10 keV Ar<sup>+</sup> ions, isolated monoatomic steps consisting of several atoms (from one to four) are formed upon it. The distances between

**•** It was shown that the analysis of the characteristic peaks appearing in energy and angular distributions of ions undergoing small-angle correlated scattering on chains of adatoms and target atoms on the single-crystal surface and comparison with experiment gives an opportunity to control the initial stages of adsorption and identification of adsorption

**•** A comparison of the angular and energy distributions of ions scattered from the surface of an alloy in the process of ordering with similar distributions for pure targets made up of the alloy components permits a conclusion that two or more neighboring atoms in an alternating sequence are of the same species. The results obtained can be used to study a short-range

**•** Sputtering yields of Cu3Au(001), Si(001), and SiC(001) surfaces versus the initial energy of incident ions (*E* 0 = 0.5–5 keV), angle of incidence (*ψ* = 0–30°), and azimuth angle of incidence

realistic evaluation of its capabilities.

on a single-crystal surface.

the steps vary from two lattice constants to ~45 Å.

structures with the help of low-energy ion scattering.

order in alloys undergoing ordering.

**5. Conclusion**

388 Radiation Effects in Materials

Farid F. Umarov1\* and Abdiravuf A. Dzhurakhalov2

