Wang, ZhaojinWang, TianyuZhang, ChiHumphrey, Mark2021-06-111463-9076http://hdl.handle.net/1885/237288Fluorenyl-tethered o-carborane derivatives (Fl-Cb) as both mono- and di-aryl Cb assemblies were synthesized from the corresponding alkyne and B10H12(Et2S)2 in ca. 60% yields. Crystallographic studies of di-aryl examples show rigid head-to-tail or tail-to-tail packing, while for the mono-aryl examples, only loose packing was observed. In solution, the Fl-Cb compounds exhibit strong quenching of their emission, while aggregation in a mixed solvent results in an enhanced, but still weak, emission [0.11 quantum efficiency (F)]. Crystallization-induced emission was observed with the di-aryl examples [F up to 0.95]. The excitation spectra are broadened, consistent with considerable orbital degeneracy within the crystals. Theoretical calculations suggest that the inherent orbital degeneracy and the highly-ordered crystalline aggregates contribute to the excellent crystallization-induced emission in these Fl-Cb compounds.We thank the National Natural Science Foundation of China (No. 21502072), the Natural Science Foundation of Jiangsu Province (No. BK20140140), the Chinese Government Ministry of Education and State Administration of Foreign Experts Affairs Program of Introducing Talents of Discipline to Universities (111 Project B13025), and the Australian Research Council for support.application/pdfen-AU© the Owner Societies 2017201710.1039/c7cp02118f2020-11-23