Selective adsorption

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Selective adsorption is the effect when minima associated with bound-state resonances occur in specular intensity in atom-surface scattering.

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Discovery

Pronounced intensity minima were first observed in 1930 by Estermann, Frisch, and Stern, during a series of gas-surface interaction experiments attempting to demonstrate the wave nature of atoms and molecules. The phenomenon has been explained in 1936 by Lennard-Jones and Devonshire in terms of resonant transitions to bound surface states.

Significance

The selective adsorption binding energies can supply information on the gas-surface interaction potentials by yielding the vibrational energy spectrum of the gas atom bound to the surface. Starting from the 1970s, it has been extensively studied, both theoretically and experimentally. Energy levels measured with this technique are available for many systems.

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Helium-3 surface spin echo (HeSE) is an inelastic scattering technique in surface science that has been used to measure microscopic dynamics at well-defined surfaces in ultra-high vacuum. The information available from HeSE complements and extends that available from other inelastic scattering techniques such as neutron spin echo and traditional helium-4 atom scattering (HAS).

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