Diamondoid
A diamondoid, in the context of building materials for nanotechnology components, most generally refers to structures that resemble diamond in a broad sense: namely, strong, stiff structures containing dense, 3-D networks of covalent bonds, formed chiefly from first and second row atoms with a valence of three or more. Examples of diamondoid structures would include crystalline diamond, sapphire, and other stiff structures similar to diamond but with various atom substitutions which might include N, O, Si, S, and so forth. Sp²-hybridized carbon structures that – in contrast to sp³-hybridized carbon in diamond – arrange in planar sheets ("graphene" sheets) are sometimes also included in the class of diamondoid materials for nanotechnology, e.g., graphite, carbon nanotubes consisting of sheets of carbon atoms rolled into tubes, spherical buckyballs and other graphene structures.
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