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Adsorption Phenomena

  • M.-C. Desjonquères
  • D. Spanjaard
Part of the Springer Series in Surface Sciences book series (SSSUR, volume 30)

Abstract

In surface physics, the term adsorption usually means accumulation at the solid-vapour interface of atoms or molecules coming from the vapour. The most important quantity for the description of this phenomenon is the binding energy of the adsorbate i.e., the energy released when an atom of the vapour, at rest, sticks onto the surface. Adsorption phenomena are commonly classified according to the value of this binding energy:
  • the domain of physisorption corresponds to small binding energies. In this domain, the substrate-adsorbate interactions are mainly due to Van der Waals forces and involve almost no mixing between the orbitals of the adsorbate and the substrate.

  • the domain of chemisorption corresponds to large binding or adsorption energies. In this case, a bond, very similar to a chemical bond, is formed between the adsorbate and the substrate. This bond can be either covalent (sharing of electrons) or ionic (electronic transfer).

Keywords

Adsorption Energy Effective Medium Theory Isosteric Heat Weak Coupling Limit Strong Coupling Limit 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag Berlin Heidelberg 1993

Authors and Affiliations

  • M.-C. Desjonquères
    • 1
  • D. Spanjaard
    • 2
  1. 1.National de la Recherche Scientifique Service de Recherche sur les Surfaces et l’Irradiation de la MatièreCentre d’Etudes de SaclayFrance
  2. 2.National de la Recherche Scientifique Laboratoire de Physique des SolidesUniversité Paris-Sud Centre d’OrsayFrance

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