Conductance in nanotube Y-junctions

We characterise the electronic properties of triangulenes and study their use as building blocks in nanotube metallic Y-junctions. We calculate the ballistic conductance of such junctions using the Landauer formalism, and identify the existence of a non-conduction energy window when the system has a C-3 axis centered on a six-membered ring. Such a system can exploit a local C-6 symmetry to stabilize the central region of the Y-junction, thereby opening a band gap. (C) 1999 Elsevier Science B.V. All rights reserved.