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.