10.1021/jp4100262.s001
Manabu Kiguchi
Manabu
Kiguchi
Yuuta Takahashi
Yuuta
Takahashi
Shintaro Fujii
Shintaro
Fujii
Masayoshi Takase
Masayoshi
Takase
Tomoyuki Narita
Tomoyuki
Narita
Masahiko Iyoda
Masahiko
Iyoda
Masayo Horikawa
Masayo
Horikawa
Yasuhisa Naitoh
Yasuhisa
Naitoh
Hisao Nakamura
Hisao
Nakamura
Additive
Electron Pathway and Nonadditive Molecular
Conductance by Using a Multipodal Bridging Compound
American Chemical Society
2014
Nonadditive Molecular Conductance
overlap resonance effect
junction
Additive Electron Pathway
conductance
electrode
scanning tunneling microscope
HOMO
TEB
Multipodal Bridging CompoundWe
electron pathways
molecule
2014-03-13 00:00:00
Journal contribution
https://acs.figshare.com/articles/journal_contribution/Additive_Electron_Pathway_and_Nonadditive_Molecular_Conductance_by_Using_a_Multipodal_Bridging_Compound/2314828
We designed and synthesized a new
quadrivial anchoring unit <b>4-TEB</b>, to construct a stable
single-molecule junction with
gold electrodes, which should have equivalent conducting electron
pathways between two electrodes. The conductances of single-molecule
junctions comprising <b>4-TEB</b> and its bidirectional counterpart <b>2-TEB</b> were determined to be 2.7 × 10<sup>–4</sup><i>G</i><sub>0</sub> (2<i>e</i><sup>2</sup>/<i>h</i>) and 5.0 × 10<sup>–5</sup><i>G</i><sub>0</sub>, respectively, by using scanning tunneling microscope
break junction (STM-BJ) techniques. The single <b>4-TEB</b> molecule
junction had higher stability and conductivity compared to those of
the single <b>2-TEB</b> molecule junction. Although the number
of electron pathways from/to the electrode to/from the molecule was
additive using the equivalent multianchoring, the conductance of the
single-molecule junction was not additive. From first-principles electronic
transport calculations, the mechanism for the new quadrivial <b>4-TEB</b> single-molecule junction involved an overlap resonance
effect to the HOMO conducting orbital, giving rise to tunneling. Using
fixed nanogap electrodes, we constructed stable molecular junctions
of <b>4-TEB</b> and observed symmetric peaks in the derivative
of the conductance–voltage (<i>G–V</i>) curves,
which were assigned to electron transport through the HOMO on the
basis of theoretical calculations.