Batzinger Kevin, Zhou Qinghai, Ye Xiang, Borguet Eric, Xiao Shengxiong, Smeu Manuel
Department of Physics, Binghamton University, Vestal, NY, USA.
The Education Ministry Key Lab of Resource Chemistry, Joint International Research Laboratory of Resource Chemistry of Ministry of Education, Shanghai Key Laboratory of Rare Earth Functional Materials, Shanghai Frontiers Science Center of Biomimetic Catalysis, and College of Chemistry and Materials Science, Shanghai Normal University, Shanghai, 200234, China.
Chemistry. 2024 Jun 17;30(34):e202400422. doi: 10.1002/chem.202400422. Epub 2024 May 22.
A previous combined experimental and theoretical study found that the position of anchoring groups on a phenanthrene (PHE) backbone played a large role in determining the single-molecule conductance of the PHE derivative. However, a consistent 0.1 G feature was found across all PHE derivatives. To understand this, the previously investigated PHE derivatives were placed flat on a simulated Au substrate with a scanning tunneling microscope (STM) tip over PHE and conductance was calculated using the non-equilibrium Green's function technique in conjunction with density functional theory (NEGF-DFT). The location of the tip was varied to find the most conductive and most energetically favorable arrangements, which did not coincide. Furthermore, the variation in conductance found in erect junctions was not present when PHE derivatives were lying flat, with all derivatives calculated to have conductance values around 0.1 G.
先前一项结合实验与理论的研究发现，菲（PHE）主链上锚定基团的位置在决定PHE衍生物的单分子电导方面起着很大作用。然而，在所有PHE衍生物中都发现了一致的0.1 G特征。为了理解这一点，将先前研究的PHE衍生物平放在模拟的金基底上，用扫描隧道显微镜（STM）针尖置于PHE上方，并结合密度泛函理论，使用非平衡格林函数技术（NEGF-DFT）计算电导。改变针尖的位置以找到导电性最佳且能量上最有利的排列方式，但这两者并不一致。此外，当PHE衍生物平躺时，直立结中发现的电导变化并不存在，所有衍生物计算得出的电导值都在0.1 G左右。
