OPTICAL-POTENTIAL IN THE SCATTERING OF HYDROGEN AND DEUTERIUM ATOMS FROM LIF AND NAF (001)

Quantitative fitting of the specular bound state resonance structure for H and D beams scattered from LiF and NaF (001) by means of a coupled channel scattering calculation are carried out. A complex potential model is introduced to handle the effects of inelastic scattering. By varying the strength of the imaginary potential, the results can be varied continuously from the elastic resonant scattering theory of Chow and Thompson [4] to the selective adsorption hypothesis of Lennard-Jones and Devonshire [7]. Taking into account the broadening effects of the beam velocity distribution and the diminution of the elastic peaks by the Debye-Waller factor, estimates of 0.8 meV and 0.9 meV are made for the imaginary potential of LiF and NaF respectively by fitting the experimental data of Finzel et al. [1]. © 1979.