Intramolecular methyl–methyl coupling on Au (111) is explored as a new on-surface protocol for edge extension in graphene nanoribbons (GNRs). Characterized by high-resolution scanning tunneling microscopy, noncontact atomic force microscopy, and Raman spectroscopy, the methyl–methyl coupling is proven to indeed proceed at the armchair edges of the GNRs, forming six-membered rings with sp³- or sp²-hybridized carbons.

中文翻译：

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探索金属表面上的分子内甲基-甲基偶联，以扩展边缘扩展的石墨烯纳米带。

Au（111）上的分子内甲基-甲基偶联被研究为石墨烯纳米带（GNRs）边缘扩展的新表面协议。以高分辨率扫描隧道显微镜，非接触原子力显微镜和拉曼光谱为特征，证明了甲基-甲基偶联确实在GNR的扶手椅边缘进行，形成了带有sp ^3-或sp ^2-杂化的六元环。碳。