Bonds in Adsorption Phenomena on Nonmetallic Surfaces

Chemical Bonds in Adsorption Phenomena on Nonmetallic Surfaces 

Homonymous ions of deviating valency (charge) may also be formed in some processes of chemisorption they will then be formed on or near the surface but may subsequently diffuse into the interior of the crystal lattice. 

There is no boundary between semiconductors and insulators the distinction has been made only for practical reasons and a arbitrary boundary has been chosen at a certain value of the electrical resistance. We may expect that also metal ions in so-called insulators can be transferred into ions of other valency or into atoms. Such reactions may proceed more easily at the surface than in the interior of the crystal and we have to be aware of this possibility in chemisorption processes. 

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