瑞士苏黎世IBM欧洲研究院Leo Gross团队报道了奇数环[13]碳及其二聚体环[26]碳。相关研究成果发表在2024年5月10日出版的《科学》。

N个碳原子的分子环（环[N]碳，或CN）是测试量子化学理论方法的优秀基准系统，也是其他富碳材料的有价值的前体。迄今为止一直难以捉摸的奇数N环碳，被预测甚至不如偶数N环碳稳定。

该文中，研究人员通过用扫描探针显微镜尖端操作十氯芴在表面上合成环[13]碳C₁₃。通过实验和理论建模阐明了C₁₃的性质。C₁₃采用具有三态基态和扭结几何结构的开壳层构型，根据分子环境的不同，其表现出不同程度的畸变和卡宾局部化。此外，研究人员制备并表征了C₁₃二聚体环[26]碳，证明了环碳及其前体作为碳同素异形体构建块的潜力。

附：英文原文

Title: The odd-number cyclo[13]carbon and its dimer, cyclo[26]carbon

Author: Florian Albrecht, Igor Ronevi, Yueze Gao, Fabian Paschke, Alberto Baiardi, Ivano Tavernelli, Shantanu Mishra, Harry L. Anderson, Leo Gross

Issue&Volume: 2024-05-10

Abstract: Molecular rings of N carbon atoms (cyclo[N]carbons, or CN) are excellent benchmarking systems for testing quantum chemical theoretical methods and valuable precursors to other carbon-rich materials. Odd-N cyclocarbons, which have been elusive to date, are predicted to be even less stable than even-N cyclocarbons. We report the on-surface synthesis of cyclo[13]carbon, C13, by manipulation of decachlorofluorene with a scanning probe microscope tip. We elucidated the properties of C13 by experiment and theoretical modeling. C13 adopts an open-shell configuration with a triplet ground state and a kinked geometry, which shows different extents of distortion and carbene localization depending on the molecular environment. Moreover, we prepared and characterized the C13 dimer, cyclo[26]carbon, demonstrating the potential of cyclocarbons and their precursors as building blocks for carbon allotropes.

DOI: ado1399

Source: https://www.science.org/doi/10.1126/science.ado1399