DYNAMIC-RESPONSE OF SURFACE ELECTRONS TO ENERGETIC IONS AT GLANCING ANGLE SCATTERING FROM CRYSTAL-SURFACES

A new method is proposed to derive the position-dependent stopping power of crystal surfaces for energetic ions from the dependence of energy loss of specularly reflected ions on the angle of incidence on the surface. The method is applied to the specular reflection of MeV ions from the (100) surfaces of NaCl, KCl, KBr, SnTe, PbTe and PbSe, and stopping powers S(p)(x), where x is the distance of the ion from the surface, are obtained. The method is also applied to the surface channelling of MeV He ions along the [100], [110] and [210] axes of SnTe and the position-dependent stopping powers S(a)(r), where r is the distance from the atomic row, are obtained.