The Effects of Embedded Dipoles in Aromatic Self-Assembled Monolayers
The Effects of Embedded Dipoles in Aromatic Self-Assembled Monolayers
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DOI：
10.1002/adfm.201500899
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发表时间：
2015-07-01
影响因子：
19
通讯作者：
Zharnikov, Michael
中科院分区：
文献类型：
--
作者：
Abu-Husein, Tarek;Schuster, Swen;Zharnikov, Michael
使用一个有代表性的模型系统，在这里的电子和结构特性的芳香族自组装单分子膜（SAMs）的描述，包含一个嵌入的，偶极基团。作为极性单元，使用嘧啶，其在分子骨架中的取向以及因此嵌入的偶极矩的方向是变化的。这些嵌入偶极自组装膜的电子和结构特性进行了彻底的分析，使用一些互补的表征技术结合量子力学建模。结果表明，这种中链取代的单层是非常有趣的，从基本和应用的角度来看，作为偶极基团被发现诱导单层内的潜在的不连续性，静电转移的核心水平的能量在该地区的上方和下方的偶极子相对于彼此。这些SAM还允许以独立于对接化学的受控方式调谐衬底功函数，并且最重要的是，不修改SAM-环境界面。
Using a representative model system, here electronic and structural properties of aromatic self-assembled monolayers (SAMs) are described that contain an embedded, dipolar group. As polar unit, pyrimidine is used, with its orientation in the molecular backbone and, consequently, the direction of the embedded dipole moment being varied. The electronic and structural properties of these embedded-dipole SAMs are thoroughly analyzed using a number of complementary characterization techniques combined with quantum-mechanical modeling. It is shown that such mid-chain-substituted monolayers are highly interesting from both fundamental and application viewpoints, as the dipolar groups are found to induce a potential discontinuity inside the monolayer, electrostatically shifting the core-level energies in the regions above and below the dipoles relative to one another. These SAMs also allow for tuning the substrate work function in a controlled manner independent of the docking chemistry and, most importantly, without modifying the SAM-ambient interface.