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Computer simulation of the reflection of a keV ion beam from a single crystal is carried out for different target temperatures. Ar ions bombarding obliquely a Cu lattice with 2 keV, and a Ni crystal with 30 keV energy are considered. The potentials used are of Born-Mayer ( A e −r/b ) and Firsov ( Br −2 ) type respectively. Uncorrelated thermal vibrations of atoms with Gaussian distribution of their displacements are taken into account. The spatial and energy distribution of the reflected ions obtained for different temperatures are discussed. The energy spectra are compared with the experimental data for the same conditions.

The reflection of argon ions with an energy of 50 to 500 eV from a copper single crystal is simulated on a digital computer. Three models are used to describe the interaction of the projectiles with the crystal: 1. the ion interacts in each moment only with the nearest crystal atom, 2. the ion interacts with all atoms of some microcrystallite whose atoms are assumed to be free, 3. the ion interacts with a microcrystallite of bound lattice atoms. For the Ar+–Cu and Cu–Cu interaction we use the Born-Mayer potential. A comparison of the results on the spatial and energy distributions of the ions in the different models is made. [Russian Text Ignored].

The scattering of Ar, Ne, and He ions from the Cu {100} face has been investigated by a digital computer technique; only binary elastic collisions of ions with the lattice atoms have been considered; the angular and energy distribution at various directions of incidence are discussed. The scattering by surface atomic chains and its contribution to the general picture of ion reflection were also studied.