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 alkeno-thiolates 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.