Study of the NaCl(001) surface by H atom scattering. I. Diffraction

High resolution diffraction measurements of 1H and 2H atomic beams from the (001) faced NaCl are presented and discussed. From the analysis of the diffracted intensity in the principal azimuthal directions, the diffraction probabilities have been obtained together with an estimate of the Debye-Waller factor. It is shown that an interpretation of the data using the hard wall interaction potential requires two Fourier components and gives the following best fitted values ? 0 = 0.328 A ? and ? 1 = 0.097 0 A ?. It is also shown that such a model is inadequate in describing the data and that the softness of the interaction plays an important role in the diffraction of atomic hydrogen. The data are also compared with other H atom experiments on alkali halides and a discussion of the differences between the H and the He probe is given.