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Ranges of H and D ions in crystalline Si and W were calculated. It is shown, that as the energy of ions increases the depth distribution of ranges splits into two components: one is connected with near-surface scattering, and the other one characterizes channeled particles. A new phenomenon was observed – a stable spatial structure of the channeled part of the beam forms after the beam passes a short distance. As the ions slow down they start to transition into adjacent channels. The spatial structure of channeled ions falls apart near the stopping point of the particles. An experiment which would connect the obtained spatial distribution with angular distribution of emitted particles is proposed.

The distribution of energy release (linear energy loss) over depth was calculated when bombarded with deuterium atoms of a tungsten target in a wide energy range of incident particles of 100 eV - 10 MeV. It is shown that in the energy range up to 100 keV, the maximum energy release, contrary to the prevailing ideas, is near the surface of a solid. At energies above 100 keV, the nature of the distribution changes and the Bragg maximum appears near the point where the particle stops. The distribution of the energy release over depth in tungsten is obtained for conditions typical of the ITER tokamak reactor, which makes it possible to estimate the wall heating during bombardment by plasma atoms.

An overview of results concerning simulation of various processes which occur due to atomic bombardment of crystalline and amorphous solids is presented. With the use of original computational codes, the following data were obtained: reflection coefficients, projected energy losses and ranges of ions in solids, channeling data as well as sputtering yield and its dependence on incident angle of bombarding particles for Be-W and Ne-W combinations. Be, C and W targets were studied as these are among the plasma-facing materials in tokamaks, including ITER. The emphasis was made on atom-target combinations which lack reliable experimental data. Experimental data on other materials were used to verify calculations. A significant influence of the interaction potential used on the simulation results is shown. The reviewed results are tied by a common subject – a study of interaction of plasma ions and first-wall materials of a tokamak-reactor – and also by a common method of study – the use of an original computational code.