Inversion of gas-surface scattering data for potential determination using functional sensitivity analysis. II. Extraction of the full interaction potential from low energy diffraction data

We demonstrate that the full gas-surface potential can be successfully recovered from low energy elastic scattering intensities within the framework of functional sensitivity analysis and Tikhonov regularization as formulated previously. Specifically, we consider an extensive, but finite, set of simulated discrete data from specular scattering and three in-plane diffraction orders over a wide range of incident polar angles for the rigid, periodic, and corrugated He-Xe/C(0001) system at fixed beam energy and fixed azimuthal angle. It is found that the potential extracted from these input data unambiguously resembles the intended model potential. The recovered potential is only slightly steeper in the upper portion of the repulsive wall, and its minima are slightly deeper. Moreover, the repulsive walls of the recovered and true potentials cross the zero at almost the same distances from the surfaces. Finally, all of the details of the input data, namely, the positions and shapes of the bound-state resonance extrema for all scattering channels under study, are accurately reproduced by the recovered potential.