Effect of the indices of crystal plane of gold electrodes on the transport properties of C20 fullerene

Using first-principles density functional theory and nonequilibrium Green’s function formalism, we investigate the effect of the indices of crystal plane of electrodes on the electronic transport properties of molecular devices by taking C20 fullerene molecule as conductor component and semi-infinite Au(111)/(100) as electrodes. The results show that the transport behaviors through molecular devices are closely related to the crystallographic orientation of electrodes. Negative differential resistance (NDR) in the current-voltage curve can be observed for the Au(100) electrode case but cannot be observed for the Au(111) case. A mechanism for the NDR phenomenon is proposed.