On the total external reflection of ions from the surface

A new approach is proposed to describe the interaction of ions with the surface enabling the calculation of the interaction energy of a particle with the surface and the determination of the critical total external reflection (TER) angle. A Fokker-Planck type kinetic equation is used to calculate angular divergence of the reflected ions beam, arising due to scattering on electrons of surface atoms and surface potential fluctuations. It is shown that at a fair initial collimation of the beam a final divergence is insignificant, therefore, by bending the surface at an apropriate radius of curvature one can effectively and multiply reflect the ions. This makes it possible to sweep the beam at angles of the order of several tens of reflection angles