Molecular π-magnets based on single organic molecules have attracted increasing attention for their potential applications in optoelectronics and spintronics. Global aromaticity in conjugated macrocyclic polyradicaloids is still an open question that has only been tackled in molecules with an even number of electrons. Here, we report the on-surface synthesis of a cyclopenta-ring-fused oligo(m-phenylene) macrocycle, 9MC, with an odd number of electrons. The generated polyradicaloid undergoes a surface-induced distortion to a D_3h symmetry with a fully delocalized doublet ground state. Interestingly, 9MC exhibits two aromatic annulene-within-an-annulene (AWA) ring currents in the inner and outer rings.

中文翻译：

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全球芳香族奇电子π磁大环


基于单个有机分子的分子π磁体因其在光电子学和自旋电子学中的潜在应用而受到越来越多的关注。共轭大环多自由基化合物中的全局芳香性仍然是一个悬而未决的问题，仅在具有偶数个电子的分子中得到解决。在这里，我们报道了具有奇数个电子的环戊环熔合寡核苷酸（间苯基）大环 9MC 的表面合成。生成的多自由基体经历表面诱导的畸变，达到 D_3h 对称性，具有完全离域双峰基态。有趣的是，9MC 在内环和外环中表现出两个芳香族环内环 （AWA） 环流。