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A 'passivated precursor' approach is developed for the efficient synthesis and isolation of all‐alkynyl‐protected gold nanoclusters. Direct reduction of dpa‐passivated precursor Au‐dpa (Hdpa=2,2'‐dipyridylamine) in one‐pot under ambient conditions gives a series of clusters including Au22(C≡CR)18 (R=−C6H4−2−F), Au36(C≡CR)24, Au44(C≡CR)28, Au130(C≡CR)50, and Au144(C≡CR)60. These clusters can be well separated via column chromatography. The overall isolation yield of this series of clusters is 40 % (based on gold), which is much improved in comparison with previous approaches. It is notable that the molecular structure of the giant cluster Au130(C≡CR)50 is revealed, which presents important information for understanding the structure of the mysterious Au130 nanoclusters. Theoretical calculations indicated Au130(C≡CR)50 has a smaller HOMO‐LUMO gap than Au130(S−C6H4−4−CH3)50. This facile and reliable synthetic approach will greatly accelerate further studies on all‐alkynyl‐protected gold nanoclusters. [ABSTRACT FROM AUTHOR]

The application of supramolecular templates in aligning atomically precise heterometal arrays is important for pursuing functional materials. Herein, we report that a bilayered supramolecular tri‐deprotonated melamine dimer functions as an effective template in the construction of a heterometallic gold(I)‐silver(I) macrocyclic cluster [μ6‐(C3N6H3)3−]2−AuI6AgI6. X‐ray single crystal structural analysis showed that a crown‐like AuI6AgI6 macrocycle is aligned around two parallelly stacked μ6‐(C3N6H3)3− moieties hold together with π–π interactions. Theoretical calculations revealed that the [μ6‐(C3N6H3)3−]2 motif dominantly contributes to the near‐occupied orbitals in the electronic structure, which is closely related to its luminescence properties. This work demonstrates that the supramolecular templates containing multiple symmetric binding sites may present a facile approach in the construction of functional metal clusters. [ABSTRACT FROM AUTHOR]

A 'passivated precursor' approach is developed for the efficient synthesis and isolation of all‐alkynyl‐protected gold nanoclusters. Direct reduction of dpa‐passivated precursor Au‐dpa (Hdpa=2,2'‐dipyridylamine) in one‐pot under ambient conditions gives a series of clusters including Au22(C≡CR)18 (R=−C6H4−2−F), Au36(C≡CR)24, Au44(C≡CR)28, Au130(C≡CR)50, and Au144(C≡CR)60. These clusters can be well separated via column chromatography. The overall isolation yield of this series of clusters is 40 % (based on gold), which is much improved in comparison with previous approaches. It is notable that the molecular structure of the giant cluster Au130(C≡CR)50 is revealed, which presents important information for understanding the structure of the mysterious Au130 nanoclusters. Theoretical calculations indicated Au130(C≡CR)50 has a smaller HOMO‐LUMO gap than Au130(S−C6H4−4−CH3)50. This facile and reliable synthetic approach will greatly accelerate further studies on all‐alkynyl‐protected gold nanoclusters. [ABSTRACT FROM AUTHOR]

The syntheses and properties of two bimetallic nanoclusters [Au4Ag23(C≡CtBu)10(dppf)4Cl7](PF6)2 and [Au5Ag24(C≡CC6H4‐p‐tBu)16(dppf)4Cl4](PF6)3 are reported. The Au atoms distributed in both the cores and the surface motifs are clearly determined. The two nanoclusters show distinctly different geometric structures and electronic properties, which are attributed to the subtle changes in the surface alkynyl structures. Cluster control: Two different alloy Au4Ag23 and Au5Ag24 nanoclusters are induced by a subtle change of the groups on their alkynyl ligands (see figure). [ABSTRACT FROM AUTHOR]

The syntheses and properties of two bimetallic nanoclusters [Au4Ag23(C≡CtBu)10(dppf)4Cl7](PF6)2 and [Au5Ag24(C≡CC6H4‐p‐tBu)16(dppf)4Cl4](PF6)3 are reported. The Au atoms distributed in both the cores and the surface motifs are clearly determined. The two nanoclusters show distinctly different geometric structures and electronic properties, which are attributed to the subtle changes in the surface alkynyl structures. Cluster control: Two different alloy Au4Ag23 and Au5Ag24 nanoclusters are induced by a subtle change of the groups on their alkynyl ligands (see figure). [ABSTRACT FROM AUTHOR]

A red-near-IR dual-emissive nanocluster with the composition [Au10Ag2(2-py−C≡C)3(dppy)6](BF4)5 ( 1; 2-py−C≡C is 2-pyridylethynyl, dppy=2-pyridyldiphenylphosphine) has been synthesized. Single-crystal X-ray structural analysis reveals that 1 has a trigonal bipyramidal Au10Ag2 core that contains a planar Au4(2-py−C≡C)3 unit sandwiched by two Au3Ag(dppy)3 motifs. Cluster 1 shows intense red-NIR dual emission in solution. The visible emission originates from metal-to-ligand charge transfer (MLCT) from silver atoms to phosphine ligands in the Au3Ag(dppy)3 motifs, and the intense NIR emission is associated with the participation of 2-pyridylethynyl in the frontier orbitals of the cluster, which is confirmed by a time-dependent density functional theory (TD-DFT) calculation. [ABSTRACT FROM AUTHOR]

The Frontispiece shows two nanoclusters are induced by the change of the surface alkynyl structures. The alkynyl −C≡C−tBu gives rise to a more spherical surface shape in 1 (red background) while −C≡CC6H4‐p‐tBu to a flat shape in 2 (green backgroud). The red and green also represent their different crystal colors and different UV/Vis properties. There are also Cl (green ball) and dppf (purple ball) surrounding these structures, suggesting co‐protection by three types of ligands. For more information, see the Full Paper Y.‐M. Lin, Q.‐M. Wang et al. on page 16029 ff. [ABSTRACT FROM AUTHOR]

The Frontispiece shows two nanoclusters are induced by the change of the surface alkynyl structures. The alkynyl −C≡C−tBu gives rise to a more spherical surface shape in 1 (red background) while −C≡CC6H4‐p‐tBu to a flat shape in 2 (green backgroud). The red and green also represent their different crystal colors and different UV/Vis properties. There are also Cl (green ball) and dppf (purple ball) surrounding these structures, suggesting co‐protection by three types of ligands. For more information, see the Full Paper Y.‐M. Lin, Q.‐M. Wang et al. on page 16029 ff. [ABSTRACT FROM AUTHOR]