Diamond fragments as building blocks of functional nanostructures

Using density functional theory, we investigate the equilibrium structure, stability, and electronic properties of nanostructured, hydrogen-terminated diamond fragments. The equilibrium atomic arrangement and electronic structure of these nanostructures turn out to be very similar to bulk diamond. We find that such diamondoids may enter spontaneously into carbon nanotubes. Polymerization inside a nanotube is favored especially when boron and nitrogen are substituted for carbon atoms.