Design and First-principles Study of a Fullerene Molecular Device

By using open-ended armchair (6, 6) single-wall carbon nanotubes as electrodes, we investigate the electron transport properties of an all-carbon molecular junction based on the C₈₂ molecule. We find the most stable system among different isomers by performing structural optimization calculations of the C₈₂ isomers and the C₈₂ extended molecules. The
calculated results show that the C₈₂--C₂(₃) isomer and the C₈₂ extended molecule with C₈₂--C_2v isomer are most stable. For the all-carbon hybrid system consisting of C₈₂--C_2v extended molecules, it is shown that the
Landauer conductance can be tuned over several orders of magnitude both
by changing the distance between two electrodes and by changing the
orientation of the C₈₂ molecule or rotating one of the tubes around the symmetry axis of the system at a fixed distance. Also, we find the most stable distance between two electrodes from the total energy curve. This fact could make this all-carbon molecular system a possible candidate for a nanoelectronic switch. Moreover, we interpret the conductance mechanism for such a molecular device.