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Due to the stability issue, It is difficult to prepare a silver nanocluster bearing functional sites, especially at a large scale. We report the synthesis and structure of a stable silver nanocluster bearing multiple surface aldehyde groups [Ag21(Ph2PO2)10(p‐CHOPhC≡C)6]SbF6, which allows for postsynthesis modification such as surface functionalization through aldimine condensation to give homochiral clusters. Remarkably, the preparation of this cluster can be done in ~90 % high yield at gram scale, which facilitates further studies and potential applications. Through DFT calculations and geometric structure analysis, the high stability of this cluster is attributed to the geometric closure and electronic structure. This is the first time that an effective one‐pot method has been developed to synthesize functional silver nanoclusters in high yield. The title cluster will be useful in the development of a variety of cluster‐based materials. [ABSTRACT FROM AUTHOR]

The reduction of alkynyl‐silver and phosphine‐silver precursors with a weak reducing reagent Ph2SiH2 led to the formation of a novel silver nanocluster [Ag93(PPh3)6(C≡CR)50]3+ (R=4‐CH3OC6H4), which is the largest structurally characterized cluster of clusters. This disc‐shaped cluster has a Ag69 kernel consisting of a bicapped hexagonal prismatic Ag15 unit wrapped by six Ino decahedra through edge‐sharing. This is the first time that Ino decahedra are used as a building block to assemble a cluster of clusters. Moreover, the central silver atom has a coordination number of 14, which is the highest in metal nanoclusters. This work provides a diverse metal packing pattern in metal nanoclusters, which is helpful for understanding metal cluster assembling mechanisms. [ABSTRACT FROM AUTHOR]

A Au55 nanocluster with the composition of [Au55(p‐MBT)24(Ph3P)6](SbF6)3 (p‐MBT=4‐methylbenzenethiolate) is synthesized via direct reduction of gold‐phosphine and gold‐thiolate precursors. Single‐crystal X‐ray diffraction reveals that this Au55 nanocluster features a face‐centered cubic (fcc) Au55 kernel, different from the well‐known two‐shell cuboctahedral arrangement in Au55(Ph3P)12Cl6. The Au55 cluster shows a wide optical absorption band with optical energy gap (Eg=1.28 eV). It is found that the exclusion of chloride is crucial for the formation of the title cluster, otherwise rod‐like [Au25(SR)5(PPh3)10Cl2]2+ is obtained. The strategy to run synthetic reaction in the absence of halide leads to new members of phosphine/thiolate co‐protected metal nanoclusters. The Au55 nanocluster exhibits high catalytic activity and selectivity for electrochemical reduction of CO2 to CO; the Faradaic efficiency (FE) reaches 94.1 % at −0.6 V vs. reversible hydrogen electrode (RHE). [ABSTRACT FROM AUTHOR]

High‐yield and large‐scale synthesis are highly demanded for the studies of gold nanoclusters. We developed a "cluster from cluster" approach to assemble gold nanoclusters with preformed atomically precise Au13 precursors. This facile approach has proved to be very effective in the synthesis of the well‐known magic cluster [Au25(SR)18]−, which could prepare the target cluster in high yield (overall yield up to ≈100 %) at large scale (gram‐scale based on gold). This method can be applied in the synthesis of 10 Au25 clusters with different R groups. This work presents an important approach that may be extended to high‐yield and large‐scale synthesis of other metal nanoclusters. [ABSTRACT FROM AUTHOR]

The first all‐amidinate‐protected gold nanocluster [Au28(Ph−form)12](OTf)2 (Ph‐form=N,N′‐diphenylformamidinate) (Au28) has been synthesized and structurally resolved. Single crystal X‐ray diffraction reveals that Au28 has a compact Au4@Au24 tetrahedral core–shell structure of T symmetry, which is fully protected by 12 bridging formamidinate ligands. This cluster is quite robust as indicated by the fact that it can stay intact in solution at 80 °C for 6 d. It exhibits excellent catalytic performance for the electroreduction of CO2 with 96.5 % Faradaic efficiency (FE) at −0.57 V and a maximum TOF of 1731 h−1 at −0.87 V. Its superior stability is also manifested in the fact that the supported catalyst Au28/CNTs maintains stable potentials at ca. −0.69 V for 40 h with FE(CO)s>91 %. A superatomic electron configuration of 1S21P62S21D4 has been clarified by DFT computations, and the strong gold–ligand binding and geometric shell closure account for the superior stability of Au28. [ABSTRACT FROM AUTHOR]

Silver nanoclusters containing Ag0 atoms protected by amino acids were synthesized and characterized. Chiral superatomic silver nanoclusters [Ag47L12(C≡CtBu)16]BF4 (L=l‐/d‐valine or l‐/d‐isoleucine) have been prepared by reducing AgC≡CtBu and amino acids (AAs) with NaBH4. Single crystal X‐ray diffraction revealed that these clusters have T symmetry, and the Ag47 metal kernel can be viewed as a tetracapped truncated tetrahedron (Ag17) surrounded with six W‐shaped Ag5 units. The clusters are homochiral as evidenced by CD measurements. As for the strong CD signals, large contributions are found from the occupied Ag s,p states (superatomic D states) near the Fermi level. Electron counting revealed that these clusters are 18‐electron systems, suggesting they are superatomic clusters. The superatomic nature with a 1S21P61D10 configuration was supported by DFT calculations. This work paves the way of taking AAs as facile chiral induction agents for the synthesis of metal nanoclusters. [ABSTRACT FROM AUTHOR]

By directly reducing alkynyl–silver precursors, we successfully obtained a large alkynyl‐protected silver nanocluster, (C7H17ClN)3[Ag112Cl6(C≡CAr)51], which is hitherto the largest structurally characterized silver nanocluster in the alkynyl family. The cluster exhibits four concentric core–shell structures (Ag13@Ag42@Ag48@Ag9), and four types of alkynyl–silver binding modes are observed. Chloride was found to be critical for the stabilization and formation of the silver nanocluster. The release of chloride ions in situ from CH2Cl2 solvent has been confirmed by mass spectrometry. This study suggests that the combination of alkynyl and halide ligands will pave a new way for the synthesis of large silver nanoclusters. [ABSTRACT FROM AUTHOR]

An alkynyl‐protected gold nanocluster, Au22(tBuC≡C)18 (1), has been synthesized and its structure has been determined by single‐crystal X‐ray diffraction. The molecular structure consists of a Au13 cuboctahedron kernel and three [Au3(tBuC≡C)4] trimeric staples. The cluster 1 has strong luminescence in the solid state with a 15 % quantum yield, and it displays interesting thermochromic luminescence as revealed by temperature‐dependent emission spectra. The enhanced room‐temperature emission is characterized as thermally activated delayed fluorescence. [ABSTRACT FROM AUTHOR]

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Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: Total structure determination of a ligand‐protected gold nanocluster, Au144, has been successfully carried out. The composition of title nanocluster is Au144(C≡CAr)60 (1; Ar=2‐FC6H4‐). The cluster 1 exhibits a quasi‐spherical Russian doll‐like architecture, comprising a Au54 two‐shelled Mackay icosahedron (Au12@Au42), which is further enclosed by a Au60 anti‐Mackay icosahedral shell. The Au114 kernel is enwrapped by thirty linear ArC≡C‐Au‐C≡CAr staple motifs. The absorption spectrum of 1 shows two bands at 560 and 620 nm. This spectrum is distinctly different from that of thiolated Au144, which was predicted to have an almost identical metal kernel and very similar ligands arrangement in 1. These facts indicate the molecule‐like behavior of 1 and significant involvement of ligands in the electronic structure of 1. The cluster 1 is hitherto the largest coinage metal nanocluster with atomically precise molecular structure in the alkynyl family. The work not only addresses the concern of structural information of Au144, which had been long‐pursued, but also provides an interesting example showing ligand effects on the optical properties of ligand protected metal nanoclusters. [ABSTRACT FROM AUTHOR]

Abstract: The controlled synthesis and structure determination of a bimetallic nanocluster Au57Ag53(C≡CPh)40Br12 (Au57Ag53) is presented. The metal core has a four‐shell Au2M3@Au34@Ag51 @Au20 (M=1/3 Au+2/3 Ag) architecture. In contrast to the previously reported large nanoclusters that have highly symmetric kernel structures, the metal atoms in Au57Ag53 are arranged in an irregular manner with C1 symmetry. This cluster exhibits excellent thermal stability and is robust under oxidative or basic conditions. The silver precursors play a key role in dictating the structures of the nanoclusters, which suggests the importance of the counteranions used. [ABSTRACT FROM AUTHOR]

For the first time total structure determination of homoleptic alkynyl-protected gold nanoclusters is reported. The nanoclusters are synthesized by direct reduction of PhC≡CAu, to give Au44(PhC≡C)28 and Au36(PhC≡C)24. The Au44 and Au36 nanoclusters have fcc-type Au36 and Au28 kernels, respectively, as well as surrounding PhC≡C-Au-C2(Ph)Au-C≡CPh dimeric 'staples' and simple PhC≡C bridges. The structures of Au44(PhC≡C)28 and Au36(PhC≡C)24 are similar to Au44(SR)28 and Au36(SR)24, but the UV/Vis spectra are different. The protecting ligands influence the electronic structures of nanoclusters significantly. The synthesis of these two alkynyl-protected gold nanoclusters indicates that a series of gold nanoclusters in the general formula Au x(RC≡C) y as counterparts to Au x(SR) y can be expected. [ABSTRACT FROM AUTHOR]

An alkynyl-protected gold nanocluster [Au24(CCPh)14(PPh3)4](SbF6)2 has been prepared by a direct reduction method. Single-crystal X-ray diffraction reveals that the molecular structure contains a Au22 core that is made of two Au13-centered cuboctahedra that share a square face. Two staple-like PhCCAuCCPh motifs are located around the center of the rod-like Au22 core. This Au24 nanocluster is highly emissive in the near-infrared region with λmax=925 nm and the nature of the HOMO-LUMO transition is investigated by time-dependent DFT calculations. [ABSTRACT FROM AUTHOR]

The chirality of a gold nanocluster can be generated from either an intrinsically chiral inorganic core or an achiral inorganic core in a chiral environment. The first structural determination of a gold nanocluster containing an intrinsic chiral inorganic core is reported. The chiral gold nanocluster [Au20(PP3)4]Cl4 (PP3=tris(2-(diphenylphosphino)ethyl)phosphine) has been prepared by the reduction of a gold(I)-tetraphosphine precursor in dichloromethane solution. Single-crystal structural determination reveals that the cluster molecular structure has C3 symmetry. It consists of a Au20 core consolidated by four peripheral tetraphosphines. The Au20 core can be viewed as the combination of an icosahedral Au13 and a helical Y-shaped Au7 motif. The identity of this Au20 cluster is confirmed by ESI-MS. The chelation of multidentate phosphines enhances the stability of this Au20 cluster. [ABSTRACT FROM AUTHOR]

For the first time total structure determination of homoleptic alkynyl-protected gold nanoclusters is reported. The nanoclusters are synthesized by direct reduction of PhC≡CAu, to give Au44(PhC≡C)28 and Au36(PhC≡C)24. The Au44 and Au36 nanoclusters have fcc-type Au36 and Au28 kernels, respectively, as well as surrounding PhC≡C-Au-C2(Ph)Au-C≡CPh dimeric 'staples' and simple PhC≡C bridges. The structures of Au44(PhC≡C)28 and Au36(PhC≡C)24 are similar to Au44(SR)28 and Au36(SR)24, but the UV/Vis spectra are different. The protecting ligands influence the electronic structures of nanoclusters significantly. The synthesis of these two alkynyl-protected gold nanoclusters indicates that a series of gold nanoclusters in the general formula Au x(RC≡C) y as counterparts to Au x(SR) y can be expected. [ABSTRACT FROM AUTHOR]

High‐yield and large‐scale synthesis are highly demanded for the studies of gold nanoclusters. We developed a "cluster from cluster" approach to assemble gold nanoclusters with preformed atomically precise Au13 precursors. This facile approach has proved to be very effective in the synthesis of the well‐known magic cluster [Au25(SR)18]−, which could prepare the target cluster in high yield (overall yield up to ≈100 %) at large scale (gram‐scale based on gold). This method can be applied in the synthesis of 10 Au25 clusters with different R groups. This work presents an important approach that may be extended to high‐yield and large‐scale synthesis of other metal nanoclusters. [ABSTRACT FROM AUTHOR]

By directly reducing alkynyl–silver precursors, we successfully obtained a large alkynyl‐protected silver nanocluster, (C7H17ClN)3[Ag112Cl6(C≡CAr)51], which is hitherto the largest structurally characterized silver nanocluster in the alkynyl family. The cluster exhibits four concentric core–shell structures (Ag13@Ag42@Ag48@Ag9), and four types of alkynyl–silver binding modes are observed. Chloride was found to be critical for the stabilization and formation of the silver nanocluster. The release of chloride ions in situ from CH2Cl2 solvent has been confirmed by mass spectrometry. This study suggests that the combination of alkynyl and halide ligands will pave a new way for the synthesis of large silver nanoclusters. [ABSTRACT FROM AUTHOR]

Abstract: Total structure determination of a ligand‐protected gold nanocluster, Au144, has been successfully carried out. The composition of title nanocluster is Au144(C≡CAr)60 (1; Ar=2‐FC6H4‐). The cluster 1 exhibits a quasi‐spherical Russian doll‐like architecture, comprising a Au54 two‐shelled Mackay icosahedron (Au12@Au42), which is further enclosed by a Au60 anti‐Mackay icosahedral shell. The Au114 kernel is enwrapped by thirty linear ArC≡C‐Au‐C≡CAr staple motifs. The absorption spectrum of 1 shows two bands at 560 and 620 nm. This spectrum is distinctly different from that of thiolated Au144, which was predicted to have an almost identical metal kernel and very similar ligands arrangement in 1. These facts indicate the molecule‐like behavior of 1 and significant involvement of ligands in the electronic structure of 1. The cluster 1 is hitherto the largest coinage metal nanocluster with atomically precise molecular structure in the alkynyl family. The work not only addresses the concern of structural information of Au144, which had been long‐pursued, but also provides an interesting example showing ligand effects on the optical properties of ligand protected metal nanoclusters. [ABSTRACT FROM AUTHOR]