Ground-state electronic structure of nanoscale carbon cones

The electronic properties of open- and closed-apex carbon nanocones are investigated systematically using a suitable sp tight-binding Hamiltonian. Our local approach is able to describe locally the electronic properties as a function of size and symmetry. We found that the symmetry of the edge sites at the open apex (zig-zag or armchair) plays a crucial role in the determination of the electronic structure. The effect of the curvature when studying closed tips containing pentagons, heptagons, and hexagons was also investigated. Finite-size effects are also discussed and the results are compared to previous studies.