Soft potential and van der Waals effects in He-KCl(001) fast atom diffraction

G. A. BOCAN; A. MOMENI; M. S. GRAVIELLE; S. SZILASI; E. A. SÁNCHEZ; H. BREISS; E. M. STAICU CASAGRANDE; H. KHEMLICHE

Heisinki

Conferencia; 29th International conference on atomic collisions in solids & 11th International symposium on swift heavy ions in matter (ICACS & SHIM 2022); 2022

ICACS & SHIM 2022 Committee

In our poster we address, both experimentally and theoretically, the very grazing scatter-ing of He atoms off KCl(001), for incidence along the h100i channel. Our theoretical modelcombines a semiquantum description of the scattering dynamics and a high-precision interac-tion potential. By means of a thorough analysis of the quantum phase for in-plane scatteringand rainbow trajectories, we are able to connect the presence of a physisorption well with thesignificant enhancements of the corrugation and rainbow angle, relative to the hard corrugatedwall predictions. We trace this connection to soft potential effects on the incident and scatteredbeams due to their traversing of the physisorption well. Finally, we show that the inclusion ofvdW interactions in the potential improves the theoretical accord with experiments for both thecorrugation and the rainbow angle [1].