清华大学王泉明团队开发了与四齿甲酰胺配体结合的面心立方银纳米团簇。相关研究成果于2022年10月13日发表于国际顶尖学术期刊《美国化学会杂志》。

具有面心立方（fcc）金属核的纳米团簇由于其与大块金属的结构相似性而受到越来越多的关注。

研究证明，使用四齿甲酰胺配体有助于构建两个fcc银纳米团簇： [Ag52(5-F-dpf)16Cl4](SbF6)2 (Ag52, 5-F-Hdpf =N,N′-二（5-氟-2-吡啶基）甲酰胺）和[Ag53(5-Me-dpf)18](NO3)5 (Ag53, 5-Me-Hdpf = N,N′-二（5-甲基-2-吡啶基甲酰胺））。

单晶X射线结构分析表明，两个团簇中的银原子呈逐层排列，这可以看作是银的fcc堆积的一部分。酰胺配体的氮供体选择性钝化{111}面。由于dpf配体的四个N供体的线性排列，所有银原子都参与了fcc的堆积，也就是说，没有观察到短链基序。研究人员用含时密度泛函理论研究了Ag52和Ag53的特征吸收带。

该项工作为组装原子精确的fcc型纳米团簇提供了便利，并展示了酰胺类化合物作为金属纳米团簇合成中保护配体的前景。

附：英文原文

Title: Face-Centered Cubic Silver Nanoclusters Consolidated with Tetradentate Formamidinate Ligands

Author: Feng Hu, Heng-Wang Luyang, Rui-Lin He, Zong-Jie Guan, Shang-Fu Yuan, Quan-Ming Wang

Issue&Volume: October 13, 2022

Abstract: Growing attention has been paid to nanoclusters with face-centered cubic (fcc) metal kernels, due to its structural similarity to bulk metals. We demonstrate that the use of tetradentate formamidinate ligands facilitate the construction of two fcc silver nanoclusters: [Ag52(5-F-dpf)16Cl4](SbF6)2 (Ag52, 5-F-Hdpf = N,N′-di(5-fluoro-2-pyridinyl)formamidine) and [Ag53(5-Me-dpf)18](NO3)5 (Ag53, 5-Me-Hdpf = N,N′-di(5-methyl-2-pyridinyl)formamidine). Single-crystal X-ray structural analysis revealed that the silver atoms in both clusters are in a layer-by-layer arrangement, which can be viewed as a portion of the fcc packing of silver. The nitrogen donors of amidinate ligands selectively passivate the {111} facets. All silver atoms are involved in the fcc packing, that is, no staple motifs are observed due to the linear arrangement of the four N donors of the dpf ligands. The characteristic optical absorption bands of Ag52 and Ag53 have been studied with a time-dependent density functional theory. This work provides a facile access to assembling atomically precise fcc-type nanoclusters and shows the prospect of amidinates as protecting ligands in synthesizing metal nanoclusters.

DOI: 10.1021/jacs.2c07018

Source: https://pubs.acs.org/doi/10.1021/jacs.2c07018