Zhai Xiao-Yi, Zhao Liang
Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, China.
Nat Commun. 2025 Jan 6;16(1):405. doi: 10.1038/s41467-025-55842-w.
Luminescent gold(I) compounds have attracted intensive attention due to anticipated strong spin-orbit coupling (SOC) resulting from heavy atom effect of gold atoms. However, some mononuclear gold(I) compounds are barely satisfactory. Here, we unveil that low participation of gold in transition-related orbitals, caused by 6s-π symmetry mismatch, is the cause of low SOCs in monogold(I) compounds. To address this issue, we have developed a series of acceptor-donor organogold(I) luminescent compounds by incorporating a gem-digold moiety with various aryl donors. These compounds demonstrate wide-range tunable emission colors and impressive photoluminescence quantum yields of up to 78%, among the highest reported for polynuclear gold(I) compounds. We further reveal that the integration of the gem-digold moiety allows better interaction of gold 6s orbitals with aryl π orbitals, facilitates aryl-to-gold electron transfer, and reduces Pauli repulsion between digold units, finally engendering the formation of aurophilic interaction-based aggregates. Moreover, the strength of such intermolecular aurophilic interaction can be systematically regulated by the electron donor nature of aryl ligands. The formation of those aurophilic aggregates significantly enhances SOC from <10 to 239 cm and mainly accounts for high-efficiency phosphorescent emission in solid state.
发光金（I）化合物由于金原子的重原子效应导致预期的强自旋轨道耦合（SOC）而备受关注。然而，一些单核金（I）化合物并不尽如人意。在此，我们揭示6s-π对称性不匹配导致金在与跃迁相关的轨道中参与度较低，这是单金（I）化合物中SOC较低的原因。为了解决这个问题，我们通过将偕二金部分与各种芳基供体结合，开发了一系列给体-受体有机金（I）发光化合物。这些化合物展示了宽范围的可调发射颜色以及高达78%的令人印象深刻的光致发光量子产率，这在多核金（I）化合物中是报道的最高值之一。我们进一步揭示，偕二金部分的整合使金的6s轨道与芳基π轨道有更好的相互作用，促进了从芳基到金的电子转移，并减少了二金单元之间的泡利排斥，最终导致基于亲金相互作用的聚集体的形成。此外，这种分子间亲金相互作用的强度可以通过芳基配体的电子供体性质进行系统调节。这些亲金聚集体的形成显著增强SOC，从<10 cm提升至239 cm，并且主要促成了固态下的高效磷光发射。
