The incorporation of substitutional Co²⁺ impurities in [Cd₁₀S₄(SPh)₁₆]^4– (Cd₁₀) molecular clusters prepared by the self-assembly method where Na₂S is the sulfur precursor and a redox method where elemental S is the sulfur precursor is studied. The Co²⁺ ions provide unique spectroscopic and chemical handles to monitor dopant speciation during cluster formation and determine what role, if any, other cluster species play during Cd₁₀ cluster formation. In contrast to the redox method that produces exclusively surface-exchanged Co²⁺-doped Cd₁₀ (Co:Cd₁₀), the preparation of Cd₁₀ by the self-assembly method in the presence of Co²⁺ ions results in Co²⁺ incorporation at both the surface and core sites of the Cd₁₀ cluster. Electrospray ionization mass spectrometry (ESI–MS) analysis of the dopant distribution for the self-assembly synthesis of Co:Cd₁₀ is consistent with a near-Poissonian distribution for all nominal dopant concentrations albeit with reduced actual Co²⁺ incorporation. At a nominal Co²⁺ concentration of 50%, we observe incorporation of up to seven Co²⁺ ions within the Cd₁₀ self-assembled cluster compared to a maximum of only four Co²⁺ dopants in the Cd₁₀ redox clusters. The observation of up to seven Co²⁺ dopants must involve substitution of at least three core sites within the Cd₁₀ cluster. Electronic absorption spectra of the Co²⁺ ligand field transition in the heavily doped Co:Cd₁₀ clusters display clear deviation with the surface-doped Co²⁺-doped Cd₁₀ clusters prepared by the redox method. We hypothesize that the coordination of Co²⁺ and S^2– ions in solution prior to cluster formation, which is possible only with the self-assembly method, is critical to the doping of Co²⁺ ions within the Cd₁₀ cores.

中文翻译：

---

核掺杂 [(Cd1–xCox)10S4(SPh)16]4– 来自自组装路线的团簇

通过自组装方法制备的[Cd ₁₀ S ₄ (SPh) ₁₆ ] ^4– (Cd ₁₀ ) 分子簇中置换 Co ²⁺杂质的掺入，其中 Na ₂ S 是硫前体，氧化还原法制备的元素 S 是研究了硫前体。Co ²⁺离子提供独特的光谱和化学处理，以监测簇形成过程中的掺杂物形态，并确定其他簇物种在 Cd ₁₀簇形成过程中发挥的作用（如果有的话）。与仅产生表面交换的 Co ²⁺掺杂的 Cd ₁₀ (Co:Cd_{如图 10 所示}，在Co ²⁺离子存在下通过自组装方法制备 Cd ₁₀导致 Co ²⁺掺入到 Cd ₁₀簇的表面和核心位置。Co:Cd ₁₀自组装合成的掺杂剂分布的电喷雾电离质谱 (ESI-MS) 分析与所有标称掺杂剂浓度的近泊松分布一致，尽管实际 Co ²⁺掺入减少。在50%的标称 Co ²⁺浓度下，我们观察到在 Cd _{10 中}掺入多达七个 Co ²⁺离子自组装簇与Cd ₁₀氧化还原簇中最多只有四种 Co ²⁺掺杂剂相比。对多达七个 Co ²⁺掺杂剂的观察必须涉及对 Cd ₁₀簇内至少三个核心位点的替换。重掺杂的 Co:Cd ₁₀团簇中Co ²⁺配体场跃迁的电子吸收光谱与通过氧化还原法制备的表面掺杂的 Co ²⁺掺杂的 Cd ₁₀团簇显示出明显的偏差。我们假设 Co ²⁺和 S ^{2– 的配位}团簇形成之前溶液中的离子，这只有通过自组装方法才有可能，对于在 Cd ₁₀核内掺杂 Co ²⁺离子是至关重要的。