The facile synthesis and physical characterization of a meso-fluorenyl smaragdyrin monoradical 4, which is stable due to efficient spin delocalization and kinetic blocking, is reported. It has a small energy gap and can be oxidized and reduced into the respective cation and anion, showing different charge distribution and electronic absorption properties.

中文翻译：

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稳定的内消旋-氟烯基Smaragdyrin单自由基

的简便合成和的物理表征内消旋-芴smaragdyrin单价4，其是稳定的，由于高效的自旋离域和动力学阻挡报道。它的能隙小，可以被氧化还原成各自的阳离子和阴离子，表现出不同的电荷分布和电子吸收特性。