Electron transport through single conjugated organic molecules: basis set effects in ab initio calculations.

Journal Article (Journal Article)

We investigate electron transport through single conjugated molecules--including benzenedithiol, oligophenylene ethynylenes of different lengths, and a ferrocene-containing molecule sandwiched between two gold electrodes with different contact structures--by using a single-particle Green function method combined with density functional theory calculation. We focus on the effect of the basis set in the ab initio calculation. It is shown that the position of the Fermi energy in the transport gap is sensitive to the molecule-lead charge transfer which is affected by the size of basis set. This can dramatically change, by orders of magnitude, the conductance for long molecules, though the effect is only minor for short ones. A resonance around the Fermi energy tends to pin the position of the Fermi energy and suppress this effect. The result is discussed in comparison with experimental data.

Full Text

Duke Authors

Cited Authors

  • Ke, S-H; Baranger, HU; Yang, W

Published Date

  • October 2007

Published In

Volume / Issue

  • 127 / 14

Start / End Page

  • 144107 -

PubMed ID

  • 17935386

Electronic International Standard Serial Number (EISSN)

  • 1089-7690

International Standard Serial Number (ISSN)

  • 0021-9606

Digital Object Identifier (DOI)

  • 10.1063/1.2770718


  • eng