Semiempirical determination of the atom-surface interaction

The authors discuss three methods of determining V(z), the lateral average (G = 0 Fourier component) of the atom-surface interaction, from the bound state spectrum found in beam scattering. One method uses the Rydberg-Klein-Rees technique, which yields the width of the potential (i.e., separation of classical turning points) as a function of energy. This method incorporates also the known asymptotic form V approximately -C3z-3, where C3 is derived from the polarizability and dielectric function of atom and solid, respectively. The second method uses a hybrid potential, constructed from a Morse potential with shifted zero of energy connected to the asymptotic form, -C3z-3, requiring continuity of V and dV/dr. The third potential is a Lennard-Jones 3-9 interaction. Results are presented for H and He scattering from LiF and NaF. (Auth.)