The determination of the He-Cu interaction potential by atomic beam scattering

Experimental results on the intensity of helium diffraction peaks for the scattering from Cu(110) and for the selective adsorption from Cu(113) and Cu(115) are reported. The usual hard corrugated wall potential is definitely unable to fit the data. While the corrugated Morse potential, recently proposed by Armand and Manson, gives a very much better agreement. The corrugation is found to be dependent upon incident energy, in good agreement with the prediction of Hamann's calculation