Probing the electronic structure and Au-C bonding in AuC2nH (n=4-7) using photoelectron imaging spectroscopy and quantum chemical calculations
Probing the electronic structure and Au-C bonding in AuC2nH (n=4-7) using photoelectron imaging spectroscopy and quantum chemical calculations
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使用光电子成像光谱和量子化学计算探测 AuC2nH (n = 4-7) 中的电子结构和 Au-C 键合
DOI：
10.1039/d1cp05057e
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发表时间：
2022-01-20
影响因子：
3.3
通讯作者：
Dong，Changwu
中科院分区：
文献类型：
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作者：
Han，Changcai;Xiong，Xiao-Gen;Dong，Changwu
我们报告了利用光电子成像和量子化学计算对 AuC2nH (n = 4–7) 的结构和化学键进行的实验和理论相结合的研究。阴离子和中性 AuC2nH 的所有基态都具有线性几何形状。 AuC2nH (n = 4–7) 的电子亲和势 (EA) 分别为 2.063(5)、2.157(5)、2.220(5) 和 2.267(5) eV。 AuC8H− 和 AuC10H− 的光电子成像数据揭示了 Au-C 拉伸模式的主要振动进程。标题中性分子的基态伸缩频率分别为 226、193、177 和 128 cm−1。通过比较实验β值和理论分子轨道分析，我们证实CAM-B3LYP方法更适合描述此类不饱和长链有机金簇的性质。实验和 CAM-B3LYP 方法给出了 AuC2nH EA 趋势的大图。这表明EA值随着碳链长度的增加而变大，并且对于较大的n也显示出缓慢的增加。 NRT分析表明，随着碳原子数的增加，Au-C键序的变化并不明显，这些中性物质中的Au-C化学键以共价键为主。目前的研究提供了有关长链 AuC2nH− (n = 4–7) 及其相应中性对应物的丰富电子结构信息。
We report a combined experimental and theoretical study on the structures and chemical bonding of AuC2nH (n = 4–7) using photoelectron imaging and quantum chemical calculations. All the ground states of anions and neutral AuC2nH have a linear geometry. The electron affinities (EAs) are measured to be 2.063(5), 2.157(5), 2.220(5), and 2.267(5) eV for AuC2nH, n = 4–7, respectively. The photoelectron imaging data of AuC8H− and AuC10H− reveal major vibrational progressions in the Au–C stretching modes. The ground state stretching frequencies of the titled neutral molecules are 226, 193, 177, and 128 cm−1, respectively. By comparing the experimental β value and theoretical molecular orbital analysis, we confirm that the CAM-B3LYP method is more suitable for describing the properties of such unsaturated long chains organogold clusters. The experimental and CAM-B3LYP methods give a big picture of the trend in EAs of AuC2nH. This shows that the EA value becomes larger with an increase in the carbon chain length, and it also shows a slow increment for larger n. The NRT analysis shows that the change of the Au–C bond order is not obvious as the number of carbon atoms increases, and the covalent character dominates the Au–C chemical bonds in these neutral species. The current study provides a wealth of electronic structure information about long-chain AuC2nH− (n = 4–7) and their corresponding neutral counterparts.