Electron-ion/atom coincidence measurements of 3keV He+ interacting with a SiH(100)-(2×1) surface

Determination of Na submonolayer adsorption site on Cu(111) by low-energy ion blocking

“…The three basic advantages of using low-energy ion blocking to quantitatively determine a chemisorption site are as follows: ͑i͒ No prerequisite knowledge of the actual shapes of the blocking cones is required; ͑ii͒ accurate values of are not necessary since only normalized yields rather than absolute yields are needed; and ͑iii͒ the positions of the adsorbed atoms can be derived unambiguously by a triangulation procedure using incident angle scans with proper large scattering angles. The spectral interpretation, as described elsewhere, [17][18][19] is facilitated by use of ͑i͒ the simulation program SARIC, 18 which is based on the classical theory of ion scattering using a binary collision approximation ͑BCA͒, and ͑ii͒ "two-atom" molecular dynamics ͑MD͒ simulations. 20 All measurements were carried out at room temperature in a TOF-SARS spectrometer that has been described in detail elsewhere.…”

“…Ion fractions were determined by measuring the TOF spectra with and without a voltage applied to the deflection plates. 18 The sample was mounted on a conventional manipulator that provided reproducible rotation in both the azimuthal and incident angles within ±0.5°. The temperature of the sample was measured by a calibrated infrared pyrometer and a thermocouple attached to the front edge of the sample surface.…”