Time-of-flight scattering and recoiling spectrometry. I. Structure of the W(211) surface

The technique of time-of-flight scattering and recoiling spectrometry (TOF-SARS) with detection of both neutrals and ions is presented and the scattering technique is applied to structural analysis of the clean W(211) surface. The recoiling technique is applied to structural analysis of oxygen and hydrogen on this surface in the two papers (II and III) immediately following this one (I). This series of three papers emphasizes the ability to obtain direct ‘‘real-space’’ information on the relative positions of atoms in the surface region based on simple classical concepts. In this first paper, both backscattering (BS) and forward-scattering (FS) from a pulsed 4-keV ${\mathrm{Ar}}^{+}$ primary-ion beam are monitored as a function of polar beam incident angle α, polar beam exit angle β, surface azimuthal angle δ, and scattering angle θ for clean W(211). Plots of BS intensities in (α,δ) space provide scattering structural contour maps and three-dimensional scattering structural plots of the clean W(211) surface.