Direct imaging of single molecules at nanostructured interfaces is a grand challenge with potential to enable new, precise material architectures and technologies. Of particular interest are the structural morphology and spectroscopic signatures of the adsorbed molecule, where modern probes are only now being developed with the necessary spatial and energetic resolution to provide detailed information at the molecule–surface interface. Here, we directly characterize the adsorption of individual m-terphenyl isocyanide ligands on a reconstructed Au(111) surface through scanning tunneling microscopy and inelastic electron tunneling spectroscopy. The site-dependent steric pressure of the various surface features alters the vibrational fingerprints of the m-terphenyl isocyanides, which are characterized with single-molecule precision through joint experimental and theoretical approaches. This study provides molecular-level insights into the steric-pressure-enabled surface binding selectivity as well as its effect on the chemical properties of individual surface-binding ligands.

中文翻译：

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配体与重构 Au(111) 表面结合的空间效应的分子尺度可视化

纳米结构界面处单分子的直接成像是一项巨大的挑战，有可能实现新的、精确的材料结构和技术。特别令人感兴趣的是吸附分子的结构形态和光谱特征，其中现代探针现在才被开发成具有必要的空间和能量分辨率，以提供分子-表面界面的详细信息。在这里，我们通过扫描隧道显微镜和非弹性电子隧道光谱直接表征了单个间三联苯异氰化物配体在重建的 Au(111) 表面上的吸附。各种表面特征的位点依赖性空间压力改变了间三联苯异氰化物的振动指纹，通过联合实验和理论方法以单分子精度对其进行了表征。这项研究提供了对空间压力启用的表面结合选择性及其对单个表面结合配体化学性质的影响的分子水平见解。