Mishra Shantanu, Beyer Doreen, Eimre Kristjan, Ortiz Ricardo, Fernández-Rossier Joaquín, Berger Reinhard, Gröning Oliver, Pignedoli Carlo A, Fasel Roman, Feng Xinliang, Ruffieux Pascal
nanotech@surfaces Laboratory, Empa-Swiss Federal Laboratories for Materials Science and Technology, 8600, Dübendorf, Switzerland.
Center for Advancing Electronics and Department of Chemistry and Food Chemistry, Technical University of Dresden, 01062, Dresden, Germany.
Angew Chem Int Ed Engl. 2020 Jul 13;59(29):12041-12047. doi: 10.1002/anie.202002687. Epub 2020 May 18.
Triangular zigzag nanographenes, such as triangulene and its π-extended homologues, have received widespread attention as organic nanomagnets for molecular spintronics, and may serve as building blocks for high-spin networks with long-range magnetic order, which are of immense fundamental and technological relevance. As a first step towards these lines, we present the on-surface synthesis and a proof-of-principle experimental study of magnetism in covalently bonded triangulene dimers. On-surface reactions of rationally designed precursor molecules on Au(111) lead to the selective formation of triangulene dimers in which the triangulene units are either directly connected through their minority sublattice atoms, or are separated via a 1,4-phenylene spacer. The chemical structures of the dimers have been characterized by bond-resolved scanning tunneling microscopy. Scanning tunneling spectroscopy and inelastic electron tunneling spectroscopy measurements reveal collective singlet-triplet spin excitations in the dimers, demonstrating efficient intertriangulene magnetic coupling.
三角形锯齿状纳米石墨烯，如三角烯及其π扩展同系物，作为分子自旋电子学的有机纳米磁体受到了广泛关注，并可能作为具有长程磁序的高自旋网络的构建块，这具有巨大的基础和技术意义。作为朝着这些方向迈出的第一步，我们展示了共价键合三角烯二聚体的表面合成及磁性原理验证实验研究。在Au(111)上对合理设计的前驱体分子进行表面反应，可选择性地形成三角烯二聚体，其中三角烯单元要么通过其少数亚晶格原子直接连接，要么通过1,4-亚苯基间隔基隔开。二聚体的化学结构已通过键分辨扫描隧道显微镜进行了表征。扫描隧道谱和非弹性电子隧道谱测量揭示了二聚体中的集体单重态-三重态自旋激发，证明了三角烯间有效的磁耦合。
