Superatom Networks in Thiolate-Protected Gold Nanoparticles
Superatom Networks in Thiolate-Protected Gold Nanoparticles
复制标题
硫醇盐保护的金纳米颗粒中的超原子网络
DOI：
10.1002/anie.201302926
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发表时间：
2013-08-19
影响因子：
16.6
通讯作者：
Yang, Jinlong
中科院分区：
文献类型：
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作者：
Cheng, Longjiu;Yuan, Yuan;Yang, Jinlong
由于其独特的性质，直径小于2nm的硫代酸保护金纳米粒子（Au-SR）在实验和理论上都引起了人们的兴趣几何壳闭合是影响Au- sr纳米粒子稳定性的重要因素，由于Au元素的强相对论性作用，其几何形状是独一无二的。[Au102 (SR) 44]的x射线晶体结构测定表明，硫酸盐配体不是简单地钝化一个大的金核，而是形成[Au (SR) 2]和[Au2 (SR) 3]寡聚体，它们结合到一个较小的金核上，这与之前的“分而保之”模型一致随后，在[Au25 (SR) 18] À、[Au38 (SR) 24]和[Au36 (SR) 24]化合物的晶体结构中，[4-6]进一步证实了金核被[Aun (SR) n+ 1]低聚物包围的模型。除了四种结晶的Au-SR化合物外，还有多种Au-SR化合物通过实验分离和质量光谱和/或光谱测量，但尚未结晶，如[Au44 (SR) 28] 2À，[7][Au144 (SR) 60],[8][Au12 (SR) 9]+,[9][Au18 (SR) 14],[10][Au20 (SR) 16],[11][Au24 (SR) 20],[12][Au40 (SR) 24],[13][Au19 (SR) 13]，[14]和[Au68 (SR) 34].[15]实验分离得到的Au-SR化合物的结构可以用密度泛函理论（DFT）进行理论预测。基于“分割-保护”模型，[Au25 (SR) 18] À和[Au38 (SR) 24]的键基序的知识由独立于x射线晶体结构测定的DFT预测[16]给出。DFT预测已经成功地定位了许多合成化合物的结构，与实验x射线衍射和/或紫外/可见光谱相一致，例如[Au40 (SR) 24] 2À，[17][Au144 (SR) 60],[18][Au12 (SR) 9]+,[19][Au18 (SR) 14],[20][Au20 (SR) 16],[21][Au24 (SR) 20]，[22]和[Au19 (SR) 13].[23]所有这些Au-SR团簇都表现出遵循“划分和保护”模型的几何壳闭合，具有分子状电子结构，在最高已占据分子轨道和最低未占据分子轨道（HOMO-LUMO）之间存在相对较大的间隙。
Owing to their unique properties, thiolate-protected gold nanoparticles (Au-SR) with core diameters of less than 2 nm are of importance and have attracted interest both experimentally and theoretically.[1] Geometric shell closure is an important factor for the stability of Au-SR nanoparticles, and the geometries are unique as a result of the strong relativistic effects of Au element. The seminal X-ray crystal structural determination of [Au102 (SR) 44] showed that the thiolate ligands do not simply passivate a large gold core but instead form [Au (SR) 2] and [Au2 (SR) 3] oligomers that bind to a smaller gold core,[2] in agreement with the previous “divide-and-protect” model.[3] Later, in the crystal structures of [Au25 (SR) 18] À,[Au38 (SR) 24], and [Au36 (SR) 24] compounds,[4–6] the model of a gold core surrounded by [Aun (SR) n+ 1] oligomers was further confirmed. Besides the four crystallized Au-SR compounds, there are also a variety of Au-SR compounds which are experimentally isolated and measured by mass and/or optical spectra but not crystallized yet, such as [Au44 (SR) 28] 2À,[7][Au144 (SR) 60],[8][Au12 (SR) 9]+,[9][Au18 (SR) 14],[10][Au20 (SR) 16],[11][Au24 (SR) 20],[12][Au40 (SR) 24],[13][Au19 (SR) 13],[14] and [Au68 (SR) 34].[15] Structures of the experimentally isolated Au-SR compounds can be theoretically predicted by density functional theory (DFT) calculations. Based on the “divideand-protect” model, knowledge of the bonding motifs of [Au25 (SR) 18] À and [Au38 (SR) 24] was given by DFT predictions [16] independent of and in agreement with X-ray crystalstructure determination. DFT predictions have successfully located the structures for many of the synthesized compounds in agreement with the experimental X-ray diffraction and/or UV/Vis spectra, for example,[Au40 (SR) 24] 2À,[17][Au144 (SR) 60],[18][Au12 (SR) 9]+,[19][Au18 (SR) 14],[20][Au20 (SR) 16],[21][Au24 (SR) 20],[22] and [Au19 (SR) 13].[23] All of these Au-SR clusters show geometric shell closure following the “divide-and-protect” model and have molecule-like electronic structures with a relatively large gap between the highest occupied–lowest unoccupied molecular orbitals (HOMO–LUMO).