Hydrogen interstitials

Fig. 26. A schematic diagram illustrating a possible hydrogen diffusion path, as in Fig. 25. The diagram indicates the Si—H bonds, the distribution of weak Si—Si bonds that can be broken by the insertion of a hydrogen atom, and mobile hydrogen interstitial states (Street etal., 1988). 

With hydrogen, interstitial hydrides are formed, the compositions of which may vary from LaH2 to LaHs. 

Spectrosopic studies indicate that for quartz, hydrogen interstitials make up the majority of the hydrogen defects (e.g. Kronenberg 1994), whereas molecular H2O (Kronenberg et al. 1996) is the dominant hydrogen-bearing species in K-feldspar. 

Here the water molecule adsorbed on a zirconia surface oxygen vacancy, for example, dissociated reversibly into an oxygen ion occupying the vacancy, plus two interstitial or adsorbed hydrogen ions. The solubility of hydrogen interstitially into zirconia is low, 2 x 10 moles of water equivalent per mole... 

Leu B, Wipf H, Coluzzi B, Biscarini A, Mazzolai G, Mazzolai F M and Sumin V V (2003) Low-temperature Snoek-type relaxation of hydrogen interstitial atoms in Nbo,8Moo,2 , J- Alloy Compd., 356-357,322-325. 

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