Abstract :
Prior to this work, the effects of the electrode orientation and the bias voltage on the pyridine-terminated dithienylethene molecules have not been investigated, although the switching effect of the molecules have been reported experimentally. Using the first-principles density-functional theory and nonequilibrium green’s function formalism, the present study examined the switching behaviors of open-ring and closed-ring forms of pyridine-terminated dithienylethene molecules between different crystallographic orientations of electrodes and under different bias voltages. The characteristics of I–V curves are investigated, and the negative differential resistance behavior is observed for the open-ring forms with different electrodes.