Diffraction of fast helium atoms from a silver surface: surface potential probe

C.A. RÍOS RUBIANO; G.A. BOCAN; M.S. GRAVIELLE; N. BUNDALESKI; H. KHEMLICHE; P. RONCIN

Lanzhou

Conferencia; International Conference on Photonic, Electronic and Atomic Collisions; 2013

ICPEAC

Diffraction patterns produced by fast He atoms grazingly impinging on a Ag(110) surface are experimentally and theo- retically studied in order to probe an ab-initio surface potential that was obtained from accurate density-functional theory (DFT) calculations. To describe the momentum distributions of scattered projectiles we use the surface eikonal (SE) approximation, which considers the quantum interference in terms of the coherent superposition of transition amplitudes for different projectile paths, tak- ing into account the complete corrugation of the three-dimensional projectile-surface potential. From the comparison with the expe- rimental distributions we conclude that the present ab-initio DFT surface potential provides an appropriate description of the He- Ag(110) interaction.