Abstract
A comprehensive survey and data collection of experimental results achieved from diffracting beams of light gases like H, D, , , and from single-crystal surfaces (alkali halides, oxides, and graphite) is given, and it is shown that gas-surface diffraction is a valuable tool to get detailed information on the physical gas-surface potential: (a) From comparison of diffracted beam intensities with calculations in a corrugated hardwall approximation the periodic structure of the interaction potential is obtained together with information on the atomic structure at the surface. (b) From bound-state resonance investigations one gets information on the different terms of the gas-surface potential in Fourier expansion : the achieved spectrum of binding energies {} can be used to construct the main term , whereas observed splitting of degenerate bound states allows evaluation of the strength of the periodic terms . (c) from levels near the dissociation limit the constant of gas-surface long-range dispersion attraction can be determined. Finally, regarding the experimental results on and the potential well depth , two semiempirical rules are established: and . These rules allow the calculation of and from the static electric polarizability of the atom, the optical dielectric constant of the solid, and the system-independent constants , given in the text. Calculated values of for several gas-surface systems are given in a table.
DOI:https://doi.org/10.1103/RevModPhys.52.933
©1980 American Physical Society