Antiaromatic and open-shell molecules are attractive because of their distinct electronic and magnetic behaviour. However, their increased reactivity creates a challenge for probing their properties. Here, we describe the on-surface and in-solution generation and characterisation of a highly reactive antiaromatic molecule: indeno[1,2-b]fluorene (IF). In solution, we generated IF by KI-induced dehalogenation of a dibromo-substituted precursor molecule and found that IF survives for minutes at ambient conditions. Using atom manipulation at low temperatures we generated IF on Cu(111) and on bilayer NaCl. On these surfaces, we characterised IF by bond-order analysis using non-contact atomic force microscopy with CO-functionalised tips and by orbital imaging using scanning tunnelling microscopy. We found that the closed-shell configuration and antiaromatic character predicted for gas-phase IF are preserved on the NaCl film. On Cu(111), we observed significant bond-order reorganisation within the s-indacene moiety because of chemisorption, highlighting the importance of molecule surface interactions on the π-electron distribution.

中文翻译：

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研究吸附在不同表面上的抗芳香族多环烃。

抗芳香族分子和开壳分子因其独特的电子和磁性性能而具有吸引力。然而，它们增加的反应性为探测其性能提出了挑战。在这里，我们描述了高反应性抗芳族分子：茚并[1,2-b]芴（IF）的表面和溶液中的生成和表征。在溶液中，我们通过KI诱导的二溴取代的前体分子的脱卤作用生成了IF，发现IF在环境条件下可以存活数分钟。使用低温原子操作，我们在Cu（111）和双层NaCl上生成了IF。在这些表面上，我们通过使用具有CO功能化尖端的非接触原子力显微镜进行键序分析以及使用扫描隧道显微镜通过轨道成像对IF进行了表征。我们发现，对于气相中频预测的闭壳构型和抗芳烃特性保留在NaCl膜上。在Cu（111）上，我们观察到由于化学吸附作用，导致s-茚并四烯部分内的键阶重组显着，从而突出了分子表面相互作用对π电子分布的重要性。