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Identifying the Real Chemistry of the Synthesis and Reversible Transformation of AuCd Bimetallic Clusters
2022-06-25 14:52

西北工业大学姚传好团队报道了AuCd双金属团簇合成和可逆转化真实化学性质的确定。相关研究成果于2022年6月23日发表在国际顶尖学术期刊《美国化学会杂志》。

精确构建原子级精度的双金属团簇的能力为建立其结构-性质关联提供了令人兴奋的机会。然而,化学(前体的电荷状态、配体的性质、掺杂剂的数量等)决定了原子水平控制的团簇的制备一直是一个长期的挑战。

该文中,基于定义明确的Au25(SR)18簇(SR=硫醇盐),研究人员系统地研究了配体的空间位阻和电子效应、Au25(SR)18的电荷状态以及可能决定AuCd簇结构的掺杂量等因素。结果表明,当使用较小空间位阻的配体时,可以获得[Au19Cd3(SR)18],而当使用较大空间位阻的配体时,可以获得Au24Cd(SR)18。此外,在Cd掺杂过程中,带负电荷的[Au25(SR)18]容易形成[Au19Cd3(SR)18],而当使用中性Au25(SR)18作为前体时,会产生Au24Cd(SR)18。有趣的是,通过巧妙地操纵具有不同空间位阻的配体,[Au19Cd3(SR)18]和Au24Cd(SR)18之间发生可逆转化。

最重要的是,通过引入过量的掺杂剂,研究成功制备了一种新型的双金属簇Au4Cd4(SR)12,并完全确定了其总体结构。研究用密度泛函理论(DFT)计算了Au4Cd4(SR)12的电子结构和手性。该文报道的Au4Cd4(SR)12试具有手性的最小AuCd双金属簇。

附:英文原文

Title: Identifying the Real Chemistry of the Synthesis and Reversible Transformation of AuCd Bimetallic Clusters

Author: Huixin Xiang, Hao Yan, Jiaohu Liu, Ranran Cheng, Cong-Qiao Xu, Jun Li, Chuanhao Yao

Issue&Volume: June 23, 2022

Abstract: The capability of precisely constructing bimetallic clusters with atomic accuracy provides exciting opportunities for establishing their structure–property correlations. However, the chemistry (the charge state of precursors, the property of ligands, the amount of dopant, and so forth) dictating the fabrication of clusters with atomic-level control has been a long-standing challenge. Herein, based on the well-defined Au25(SR)18 cluster (SR = thiolates), we have systematically investigated the factors of steric hindrance and electronic effect of ligands, the charge state of Au25(SR)18, and the amount of dopant that may determine the structure of AuCd clusters. It is revealed that [Au19Cd3(SR)18] can be obtained when a ligand of smaller steric hindrance is used, while Au24Cd(SR)18 is attained when a larger steric hindrance ligand is used. In addition, negatively charged [Au25(SR)18] is apt to form [Au19Cd3(SR)18] during Cd doping, while Au24Cd(SR)18 is produced when neutral Au25(SR)18 is used as a precursor. Intriguingly, the reversible transformation between [Au19Cd3(SR)18] and Au24Cd(SR)18 is feasible by subtly manipulating ligands with different steric hindrances. Most importantly, by introducing the excess amount of dopant, a novel bimetallic cluster, Au4Cd4(SR)12 is successfully fabricated and its total structure is fully determined. The electronic structures and the chirality of Au4Cd4(SR)12 have been elucidated by density functional theory (DFT) calculations. Au4Cd4(SR)12 reported herein represents the smallest AuCd bimetallic cluster with chirality.

DOI: 10.1021/jacs.2c05053

Source: https://pubs.acs.org/doi/10.1021/jacs.2c05053

 

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