Length Dependence of Electronic Transport in Carbon Nanowires

The transport properties of oligo(ethyne) dithiolates coupled with gold electrodes is calculated using the non-equilibrium Green’s functions technique. The effect of molecular wire length on current-voltage characteristics for (-C≡C-)n n = 1-5 is investigated. The calculated decay coefficient at low bias voltage is (0.025 ± 0.002 Ǻ-1) which is found to be lower than that of alkanthiols. Results reveal that the HOMO-LUMO gap of the oligo(ethyne)s are correlated to the reciprocal of the number of triple bonds