Metalloid interstitial atoms

An interstitial compound consists of a metal or metals and certain metalloid elements, in which the metalloid atoms occupy the interstices between the atoms of the metal lattice. Compounds of this type are, for example. TaC, TiC, ZrC. NbC, and similar compounds of carbon, nitrogen, boron, and hydrogen with metals. 

Interstitial structures are composed by atoms of transitional metals with compact lattice and metalloids of small dimensions as H, B, C, N, which occupy the holes of a compact lattice. 

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