The influence of thermal fluctuations on the electronic transport of alkeno-thiolates

In this paper, we investigate the influence of molecular vibrations on the tunneling of electrons through alkenothiolates of varying lengths sandwiched in between two gold contacts. The study is confined to the elastic scattering. The vibrational modes are treated quantum-mechanically and the tunneling current is computed as an ensemble average over the distribution of the atomic configurations, obtained by a suitable approximation of the density matrix for the normal mode oscillators. The quantum-mechanical treatment is necessary in order to correctly include the zero-point fluctuations. The calculations show no temperature dependence for the tunneling current in the regime between 270-350 K.