Elucidating the Binding Modes of N-Heterocyclic Carbenes on a Gold Surface
Elucidating the Binding Modes of N-Heterocyclic Carbenes on a Gold Surface
复制标题
DOI：
10.1021/jacs.8b06180
复制
发表时间：
2018-09-26
影响因子：
15
通讯作者：
Fuchs, Harald
中科院分区：
文献类型：
--
作者：
Bakker, Anne;Timmer, Alexander;Fuchs, Harald
调整n -杂环碳烯在金属表面的结合模式对于开发新型功能材料至关重要。为了了解烷基侧基对Au（111）表面NHC物质形成的影响，我们结合了扫描隧道显微镜、x射线光电子能谱和密度泛函理论计算。我们揭示了两种明显不同的结合模式，这取决于烷基链的长度。在短烷基取代基的情况下，具有一个金原子的直立构型是优选的，而较长的烷基只导致NHC-Au-NHC配合物平躺在表面上。我们的研究强调了NHCs的明确结构修饰如何允许控制表面上的局部结合基序，这对于在界面上设计指定的催化位点非常重要。
Tuning the binding mode of N-heterocyclic carbenes on metal surfaces is crucial for the development of new functional materials. To understand the impact of alkyl side groups on the formation of NHC species at the Au(111) surface, we combined scanning tunneling microscopy, X-ray photoelectron spectroscopy, and density functional theory calculations. We reveal two significantly different binding modes depending on the alkyl chain length. In the case of a short alkyl substituent, an up-standing configuration with one Au adatom is preferred, whereas the longer alkyl groups result exclusively in NHC-Au-NHC complexes lying flat on the surface. Our study highlights how well-defined structural modifications of NHCs allow for controlling the local binding motif on surfaces, which is important to design designated catalytic sites at interfaces.