Vibronic effects on resonant electron conduction through single molecule junctions

• Published in: Chemical physics letters 2006-10, Vol.430 (4), p.355-360
• Main Authors: Benesch, C., Čížek, M., Thoss, M., Domcke, W.
• Format: Article
• Language: English
• ISSN: 0009-2614; 1873-4448
• DOI: 10.1016/j.cplett.2006.09.003

The influence of vibrational motion on electron conduction through π-conjugated molecules is investigated employing first-principles electronic-structure calculations and projection-operator Green’s function methods. It is shown that electronic–vibrational coupling may result in pronounced vibrational substructures in the transmittance, a significantly reduced current as well as a quenching of negative differential resistance effects. The influence of vibrational motion on electron conduction through single molecules bound to metal electrodes is investigated employing first-principles electronic-structure calculations and projection-operator Green’s function methods. Considering molecular junctions where a central phenyl ring is coupled via (alkane)thiol-bridges to gold electrodes, it is shown that – depending on the distance between the electronic π-system and the metal – electronic–vibrational coupling may result in pronounced vibrational substructures in the transmittance, a significantly reduced current as well as a quenching of negative differential resistance effects.