Atomic Vacancy, Nanocavity, and Porous Foams

Bonds between undercoordinated atoms in the inner surfaces of nanopores perform the same as those in the skins of the bulk arul of a nanosolid. 

A broken bond not only serves as a center initiating mechanical failure but also provides a site pinning dislocations and trapping energy. 

Atomic vacancies, point defects, and nanometer-sized pores result in the unusual properties of the specimens—they are of lightweight and high strength yet thermally or chemically less stable. 

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