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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]

A gold(I)‐cluster‐based twin‐cage has been constructed by post‐clustering covalent modification of a hexa‐aldehyde cluster precursor with triaminotriethylamines. The cages‐on‐cluster structure has double cavities and four binding sites, which show site‐discriminative binding for silver(I) and copper(I) guests. The guests in the tripodal hats affect the luminescence of the cluster: the tetra‐silver(I) host–guest complex is weakly red‐emissive, while the bis‐copper(I)‐bis‐silver(I) one is non‐emissive but is a stimuli‐responsive supramolecule. The copper(I) ion inside the tri‐imine cavity is oxidation sensitive, which enables the release of the bright emissive precursor cluster triggered by H2O2 solution. The hybridization of a cluster with cavities to construct a cluster‐based cage presents an innovative concept for functional cluster design, and the post‐clustering covalent modification opens up new avenues for finely tuning the properties of clusters. [ABSTRACT FROM AUTHOR]

A gold(I)‐cluster‐based twin‐cage has been constructed by post‐clustering covalent modification of a hexa‐aldehyde cluster precursor with triaminotriethylamines. The cages‐on‐cluster structure has double cavities and four binding sites, which show site‐discriminative binding for silver(I) and copper(I) guests. The guests in the tripodal hats affect the luminescence of the cluster: the tetra‐silver(I) host–guest complex is weakly red‐emissive, while the bis‐copper(I)‐bis‐silver(I) one is non‐emissive but is a stimuli‐responsive supramolecule. The copper(I) ion inside the tri‐imine cavity is oxidation sensitive, which enables the release of the bright emissive precursor cluster triggered by H2O2 solution. The hybridization of a cluster with cavities to construct a cluster‐based cage presents an innovative concept for functional cluster design, and the post‐clustering covalent modification opens up new avenues for finely tuning the properties of clusters. [ABSTRACT FROM AUTHOR]

A bowl-shaped phosphangulene-protected cubic Cu58 nanocluster has been synthesized. The structure was determined by X-ray crystallography and further analyzed by multiple techniques. The phosphangulenes not only enable ligand substitutions with triphenylphosphines in a cluster-to-cluster transformation way, but also facilitate inter-cluster interactions with fullerenes. These interactions further influence the entirety's photocurrent response and ability to liberate hydrogen when stimulated by light. [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]

Structurally precise metal nanoclusters with a facile synthetic process and high catalytic performance have been long pursued. These atomically precise nanocatalysts are regarded as model systems to study structure-performance relationships, surface coordination chemistry, and the reaction mechanism of heterogeneous metal catalysts. Nevertheless, the research on silver-based nanoclusters for driving chemical transformations is sluggish in comparison to gold counterparts. Herein, we report the one-step synthesis of Pt/Ag alloy nanoclusters of [PtAg9(C18H12Br3P)7Cl3](C18H12Br3P), which are highly active in catalysing cycloaddition reactions of CO2 and epoxides. The cluster was obtained in a rather simple way with the reduction of silver and platinum salts in the presence of ligands in one pot. The molecular structure of the titled cluster describes the protection of the Pt-centred Ag9 crown by the shell of phosphine ligands and halides. Its electronic structure, as revealed by density function theoretical calculations, adopts a superatomic geometry with 1S21P6 configuration. Interestingly, the cluster displays high activity in the formation of cyclic carbonates from CO2 under mind conditions. [ABSTRACT FROM AUTHOR]

Photocatalytic organic conversion is considered an efficient, environmentally friendly, and energy-saving strategy for organic synthesis. In recent decades, the molecular cage has emerged as a creative functional material with broad applications in host–guest recognition, drug delivery, catalysis, intelligent materials and other fields. Based on the unique properties of porous molecular cage materials, they provide an ideal platform for leveraging pre-structuring in catalytic reactions and show great potential in various photocatalytic organic reactions. As a result, they have emerged as promising alternatives to conventional molecules or inorganic photocatalysts in redox processes. In this Review, the synthesis strategies based on coordination cages and organic cages, as well as their recent progress in photocatalytic organic conversion, are comprehensively summarized. Finally, we deliver the persistent challenges associated with porous molecular cage compounds that need to be overcome for further development in this field. [ABSTRACT FROM AUTHOR]

A facile strategy that directly reduces alkynyl‐silver precursors and copper salts for the synthesis of bimetallic nanoclusters using the weak reducing agent Ph2SiH2 is demonstrated. Two alkynyl‐protected concentric‐shell nanoclusters, (Ph4P)2[Ag22Cu12(C≡CR)28] and (Ph4P)3[Ag42Cu12Cl(C≡CR)36] (Ag22Cu12 and Ag42Cu12Cl, R=bis(trifluoromethyl)phenyl), were successfully obtained and characterized by single‐crystal X‐ray diffraction and electro‐spray ionization mass spectrometry. For the first time, a hybrid 55‐atom two‐shell Mackay icosahedron was found in Ag42Cu12Cl, which is icosahedral M54Cl instead of M55. The incorporation of a chloride in the metal icosahedron contributes to the stability of the cluster from both electronic and geometric aspects. Alkynyl ligands show various binding‐modes including linear "RC≡C−Cu−C≡CR" staple motifs. [ABSTRACT FROM AUTHOR]

Functionalizing porous materials with capping agents generates hybrid materials with enhanced properties, while the challenge is how to improve the selectivity and maintain the porosity of the parent framework. Herein, we developed a "Cage-on-MOF" strategy to tune the recognition and catalytic properties of MOFs without impairing their porosity. Two types of porous coordination cages (PCCs) of opposite charges containing secondary binding groups were developed to coordinatively functionalize two distinct porous MOFs, namely MOF@PCC nanocomposites. We demonstrated that the surface-capped PCCs can act as "modulators" to effectively tune the surface charge, stability, and adsorption behavior of different host MOF particles. More importantly, the MOF@PCCs can serve as selective heterogeneous catalysts for condensation reactions to achieve reversed product selectivity and excellent recyclability. This work sets the foundation for using molecular cages as porous surface-capping agents to functionalize and manipulate another porous material, without affecting the intrinsic properties of the parent framework. Functionalising porous materials is a route to enhancing properties of hybrid materials. Here authors present a "Cage-on-MOF" strategy to modify the surface of mesoporous MOFs by using molecular cages to achieve selective dyes adsorption behavior and heterogeneous catalysis. [ABSTRACT FROM AUTHOR]

Mimicking the active site and the substrate binding cavity of the enzyme to achieve specificity in catalytic reactions is an essential challenge. Herein, porous coordination cages (PCCs) with intrinsic cavities and tunable metal centers have proved the regulation of reactive oxygen species (ROS) generating pathways as evidenced by multiple photo‐induced oxidations. Remarkably, in the presence of the Zn4‐μ4‐O center, PCC converted dioxygen molecules from triplet to singlet excitons, whereas the Ni4‐μ4‐O center promoted the efficient dissociation of electrons and holes to conduct electron transfer towards substrates. Accordingly, the distinct ROS generation behavior of PCC‐6‐Zn and PCC‐6‐Ni enables the conversion of O2 to 1O2 and O2⋅−, respectively. In contrast, the Co4‐μ4‐O center combined the 1O2 and O2⋅− together to generate carbonyl radicals, which in turn reacted with the oxygen molecules. Harnessing the three oxygen activation pathways, PCC‐6‐M (M=Zn/Ni/Co) display specific catalytic activities in thioanisole oxidation (PCC‐6‐Zn), benzylamine coupling (PCC‐6‐Ni), and aldehyde autoxidation (PCC‐6‐Co). This work not only provides fundamental insights into the regulation of ROS generation by a supramolecular catalyst but also demonstrates a rare example of achieving reaction specificity through mimicking natural enzymes by PCCs. [ABSTRACT FROM AUTHOR]

Mimicking the active site and the substrate binding cavity of the enzyme to achieve specificity in catalytic reactions is an essential challenge. Herein, porous coordination cages (PCCs) with intrinsic cavities and tunable metal centers have proved the regulation of reactive oxygen species (ROS) generating pathways as evidenced by multiple photo‐induced oxidations. Remarkably, in the presence of the Zn4‐μ4‐O center, PCC converted dioxygen molecules from triplet to singlet excitons, whereas the Ni4‐μ4‐O center promoted the efficient dissociation of electrons and holes to conduct electron transfer towards substrates. Accordingly, the distinct ROS generation behavior of PCC‐6‐Zn and PCC‐6‐Ni enables the conversion of O2 to 1O2 and O2⋅−, respectively. In contrast, the Co4‐μ4‐O center combined the 1O2 and O2⋅− together to generate carbonyl radicals, which in turn reacted with the oxygen molecules. Harnessing the three oxygen activation pathways, PCC‐6‐M (M=Zn/Ni/Co) display specific catalytic activities in thioanisole oxidation (PCC‐6‐Zn), benzylamine coupling (PCC‐6‐Ni), and aldehyde autoxidation (PCC‐6‐Co). This work not only provides fundamental insights into the regulation of ROS generation by a supramolecular catalyst but also demonstrates a rare example of achieving reaction specificity through mimicking natural enzymes by PCCs. [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]

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]

Cancer remains one of the most pressing diseases in the world. Traditional treatments, including surgery, chemotherapy, and radiotherapy still show certain limitations. Recently, numerous cancer treatments have been proposed in combination with novel materials, such as photothermal therapy, chemodynamic therapy, immunotherapy, and a combination of therapeutic approaches. These new methods have shown significant advantages in reducing side effects and synergistically enhancing anti-cancer efficacy. In addition to the above approaches, early diagnosis and in situ monitoring of lesion areas are also important for reducing side effects and improving the success rate of cancer therapy. This depends on the decent use of bioimaging technology. In this review, we mainly summarize the recent advances in porous framework materials for bioimaging and cancer therapy. In addition, we present future challenges relating to bioimaging and cancer therapy based on porous framework materials. [ABSTRACT FROM AUTHOR]

Atomically precise gold nanoclusters provide great opportunities to explore the relationship between the structure and properties of nanogold catalysts. A nanocluster consists of a metal core and a surface ligand shell, and both the core and shell have significant effects on the catalytic properties. Thanks to their precise structures, the active metal site of the clusters can be readily identified and the effects of ligands on catalysis can be disclosed. In this Minireview, we summarize recent advances in catalytic research of gold nanoclusters, emphasizing four strategies for constructing open metal sites, including by post‐treatment, the bulky ligands strategy, the surface geometric mismatch method, and heteroatom doping procedures. We also discuss the effects of ligands on the catalytic activity, selectivity, and stability of gold cluster catalysts. Finally, we present future challenges relating to gold cluster catalysis. [ABSTRACT FROM AUTHOR]

Atomically precise gold nanoclusters provide great opportunities to explore the relationship between the structure and properties of nanogold catalysts. A nanocluster consists of a metal core and a surface ligand shell, and both the core and shell have significant effects on the catalytic properties. Thanks to their precise structures, the active metal site of the clusters can be readily identified and the effects of ligands on catalysis can be disclosed. In this Minireview, we summarize recent advances in catalytic research of gold nanoclusters, emphasizing four strategies for constructing open metal sites, including by post‐treatment, the bulky ligands strategy, the surface geometric mismatch method, and heteroatom doping procedures. We also discuss the effects of ligands on the catalytic activity, selectivity, and stability of gold cluster catalysts. Finally, we present future challenges relating to gold cluster catalysis. [ABSTRACT FROM AUTHOR]

Developing hierarchical ordered systems is challenging. Using organo-macrocycles to construct metal–organic frameworks (MOFs) and porous coordination cages (PCCs) provides an efficient way to obtain hierarchical assemblies. Macrocycles, such as crown ethers, cyclodextrins, calixarenes, cucurbiturils, and pillararenes, can be incorporated within MOFs/PCCs and they also endow the resultant composites with enhanced properties and functionalities. This review summarizes recent developments of organo-macrocycle-containing hierarchical MOFs/PCCs, emphasizing applications and structure–property relationships of these hierarchically porous materials. This review provides insights for future research on hierarchical self-assembly using macrocycles as building blocks and functional ligands to extend the applications of the composites. [ABSTRACT FROM AUTHOR]

Anions have been used to regulate the structures and luminescence of heterometallic clusters. Introducing ClO4− into orange‐emissive, butterfly‐like [(C)(Au‐PPhpy2)6Ag4](BF4)6 (1, PPhpy2=bis(2‐pyridyl)phenylphosphine) leads to the formation of red‐emissive [(C)(Au‐PPhpy2)6Ag5(ClO4)3](ClO4)4 (2) with a novel trigonal bipyramidal structure; employing PhCO2− gives yellow‐emissive, hexagram‐like [(C)(Au‐PPhpy2)6Ag6(PhCO2)3](BF4)5 (3). Notably, 1 exhibits weak luminescence in CH2Cl2/CH3OH=1 : 1 (v : v) with a quantum yield (QY) of 0.05, whereas it was dramatically increased to 0.49 and 0.83 for 2 and 3, respectively. Theoretical calculation confirms that the involvement of anions in the electronic structures is responsible for the shifts of emission. The high QYs of 2 and 3 are attributed to the protection provided by ligands and anions. This work demonstrates that anions may serve as an extra designable factor beyond just counterions for functional metal clusters. [ABSTRACT FROM AUTHOR]

Anions have been used to regulate the structures and luminescence of heterometallic clusters. Introducing ClO4− into orange‐emissive, butterfly‐like [(C)(Au‐PPhpy2)6Ag4](BF4)6 (1, PPhpy2=bis(2‐pyridyl)phenylphosphine) leads to the formation of red‐emissive [(C)(Au‐PPhpy2)6Ag5(ClO4)3](ClO4)4 (2) with a novel trigonal bipyramidal structure; employing PhCO2− gives yellow‐emissive, hexagram‐like [(C)(Au‐PPhpy2)6Ag6(PhCO2)3](BF4)5 (3). Notably, 1 exhibits weak luminescence in CH2Cl2/CH3OH=1 : 1 (v : v) with a quantum yield (QY) of 0.05, whereas it was dramatically increased to 0.49 and 0.83 for 2 and 3, respectively. Theoretical calculation confirms that the involvement of anions in the electronic structures is responsible for the shifts of emission. The high QYs of 2 and 3 are attributed to the protection provided by ligands and anions. This work demonstrates that anions may serve as an extra designable factor beyond just counterions for functional metal clusters. [ABSTRACT FROM AUTHOR]

Surface organic ligands are critical in dictating the structures and properties of atomically precise metal nanoclusters. In contrast to the conventionally used thiolate, phosphine and alkynyl ligands, nitrogen donor ligands have not been used in the protection for well‐defined metal nanoclusters until recently. This review focuses on recent developments in atomically precise metal nanoclusters stabilized by different types of nitrogen donor ligands, in which the synthesis, total structure determination and various properties are covered. We hope that this review will provide insights into the rational design of N donor‐protected metal nanoclusters in terms of structural and functional modulation. [ABSTRACT FROM AUTHOR]

Copper hydrides are important hydrogenation catalysts, but their poor stability hinders the practical applications. Ligand engineering is an effective strategy to tackle this issue. An amidinate ligand, N,N′-Di(5-trifluoromethyl-2-pyridyl)formamidinate (Tf-dpf) with four N-donors has been applied as a protecting agent in the synthesis of stable copper hydride clusters: Cu11H3(Tf-dpf)6(OAc)2 (Cu11) with three interfacial μ5-H and [Cu12H3(Tf-dpf)6(OAc)2]·OAc (Cu12) with three interstitial μ6-H. A solvent-triggered reversible interconversion between Cu11 and Cu12 has been observed thanks to the flexibility of Tf-dpf. Cu11 shows high activity in the reduction of 4-nitrophenol to 4-aminophenol, while Cu12 displays very low activity. Deuteration experiments prove that the type of hydride is the key in dictating the catalytic activity, for the interfacial μ5-H species in Cu11 are involved in the catalytic cycle whereas the interstitial μ6-H species in Cu12 are not. This work highlights the role of hydrides with regard to catalytic hydrogenation activity. Copper hydrides have been studied for their exciting structural chemistry and applications in hydrogenation catalysis. Here, the authors uncover the role of the amidinate ligand in yielding two closely related copper hydride clusters with quite different catalytic hydrogenation activity. [ABSTRACT FROM AUTHOR]

We report the structures, stability and catalysis properties of two Ag21 nanoclusters, namely [Ag21(H2BTCA)3(O2PPh2)6]SbF6 (1) and [Ag21(C≡CC6H3‐3,5‐R2)6(O2PPh2)10]SbF6 (2) (H4BTCA=p‐tert‐butylthiacalix[4]arene, R=OMe). Both Ag21 structures possess an identical icosahedral kernel that is surrounded by eight peripheral Ag atoms. Single‐crystal structural analysis and ESI‐MS revealed that 1 is an 8‐electron cluster and 2 has four free electrons. Theoretical results show that the P‐symmetry orbitals are found as HOMO‐1 and HOMO states in 1, and the frontier unoccupied molecular orbitals (LUMO, LUMO+1 and LUMO+2) show D‐character, indicating 1 is a superatomic cluster with an electronically closed shell 1S21P6, while 2 has an incomplete shell configuration 1S21P2. These two Ag21 clusters show superior stability under ambient conditions, and 1 is robust even at 90 °C in toluene and under oxidative conditions (30 % H2O2). Significantly, 2 exhibits much higher activity than 1 as catalyst in the reduction of 4‐nitrophenol. This work demonstrates that ligands can influence the electronic structures of silver clusters, and further affect their stability and catalytic performance. [ABSTRACT FROM AUTHOR]

We report the structures, stability and catalysis properties of two Ag21 nanoclusters, namely [Ag21(H2BTCA)3(O2PPh2)6]SbF6 (1) and [Ag21(C≡CC6H3‐3,5‐R2)6(O2PPh2)10]SbF6 (2) (H4BTCA=p‐tert‐butylthiacalix[4]arene, R=OMe). Both Ag21 structures possess an identical icosahedral kernel that is surrounded by eight peripheral Ag atoms. Single‐crystal structural analysis and ESI‐MS revealed that 1 is an 8‐electron cluster and 2 has four free electrons. Theoretical results show that the P‐symmetry orbitals are found as HOMO‐1 and HOMO states in 1, and the frontier unoccupied molecular orbitals (LUMO, LUMO+1 and LUMO+2) show D‐character, indicating 1 is a superatomic cluster with an electronically closed shell 1S21P6, while 2 has an incomplete shell configuration 1S21P2. These two Ag21 clusters show superior stability under ambient conditions, and 1 is robust even at 90 °C in toluene and under oxidative conditions (30 % H2O2). Significantly, 2 exhibits much higher activity than 1 as catalyst in the reduction of 4‐nitrophenol. This work demonstrates that ligands can influence the electronic structures of silver clusters, and further affect their stability and catalytic performance. [ABSTRACT FROM AUTHOR]

Acetelyenediide (C22−) species have been encapsulated in bimetallic and trimetallic clusters: [(AuL)6Ag7(C≡C)3](BF4)7 (2) and [(AuL)6AgCu6(C≡C)3](BF4)7 (3), L=phenylbis(2‐pyridyl)phosphine (PPhpy2). Single‐crystal X‐ray diffraction analysis revealed that they are isostructural and six silver atoms in 2 are replaced with copper in 3. Both clusters have a trefoil skeleton, which can be viewed as three trigonal bipyramidal (LAu‐C≡C‐AuL)M2Ag (M=Ag/Cu) motifs sharing a common silver atom. TDDFT calculations showed Cu‐doping significantly increases the energy level of (C2‐Cu)‐involved occupied orbital, thus inducing interesting transition coupling of dual‐emission at low temperature. This work not only provides a strategy for constructing heterometallic clusters, but also shows the prospect for pursuing novel thermochromic luminescent materials by incorporating multi‐congeneric metal components. [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]

Acetelyenediide (C22−) species have been encapsulated in bimetallic and trimetallic clusters: [(AuL)6Ag7(C≡C)3](BF4)7 (2) and [(AuL)6AgCu6(C≡C)3](BF4)7 (3), L=phenylbis(2‐pyridyl)phosphine (PPhpy2). Single‐crystal X‐ray diffraction analysis revealed that they are isostructural and six silver atoms in 2 are replaced with copper in 3. Both clusters have a trefoil skeleton, which can be viewed as three trigonal bipyramidal (LAu‐C≡C‐AuL)M2Ag (M=Ag/Cu) motifs sharing a common silver atom. TDDFT calculations showed Cu‐doping significantly increases the energy level of (C2‐Cu)‐involved occupied orbital, thus inducing interesting transition coupling of dual‐emission at low temperature. This work not only provides a strategy for constructing heterometallic clusters, but also shows the prospect for pursuing novel thermochromic luminescent materials by incorporating multi‐congeneric metal components. [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]

The synthesis and isolation of alkynyl/chloride‐protected gold nanoclusters is described. Silica gel column chromatography is effective in isolating gold nanoclusters from the as‐synthesized cluster mixture to give the clusters Na[Au25L18] (Au25), [HNEt3]3[Au67L32Cl4] (Au67), [HNEt3]4[Au106L40Cl12] (Au106), L=3,5‐bis(trifluoromethyl)‐phenylacetylide. Au67 and Au106 are new clusters; the structures were determined by X‐ray single‐crystal diffraction. Au67 contains a distorted Au18 Marks decahedron shelled by an irregular Au32 and further protected with two V‐shaped Au2L3, 13 linear AuL2 staples and 4 chlorides. Au67 is the first structurally determined 34e superatomic gold nanocluster. Au106 is composed of 106 Au atoms co‐protected by alkynyls and chlorides. It has a Au79 kernel, like in Au102(p‐MBA)44. The surface structure of Au106 includes 20 linear Au‐alkynyl staples, 5 Cl‐Au‐Cl and 2 Cl‐Au motifs. These three gold nanoclusters show size‐dependent electrochemical properties. [ABSTRACT FROM AUTHOR]

The synthesis and isolation of alkynyl/chloride‐protected gold nanoclusters is described. Silica gel column chromatography is effective in isolating gold nanoclusters from the as‐synthesized cluster mixture to give the clusters Na[Au25L18] (Au25), [HNEt3]3[Au67L32Cl4] (Au67), [HNEt3]4[Au106L40Cl12] (Au106), L=3,5‐bis(trifluoromethyl)‐phenylacetylide. Au67 and Au106 are new clusters; the structures were determined by X‐ray single‐crystal diffraction. Au67 contains a distorted Au18 Marks decahedron shelled by an irregular Au32 and further protected with two V‐shaped Au2L3, 13 linear AuL2 staples and 4 chlorides. Au67 is the first structurally determined 34e superatomic gold nanocluster. Au106 is composed of 106 Au atoms co‐protected by alkynyls and chlorides. It has a Au79 kernel, like in Au102(p‐MBA)44. The surface structure of Au106 includes 20 linear Au‐alkynyl staples, 5 Cl‐Au‐Cl and 2 Cl‐Au motifs. These three gold nanoclusters show size‐dependent electrochemical properties. [ABSTRACT FROM AUTHOR]

Gold nanoclusters with surface open sites are crucial for practical applications in catalysis. We have developed a surface geometric mismatch strategy by using mixed ligands of different type of hindrance. When bulky phosphine Ph3P and planar dipyridyl amine (Hdpa) are simultaneously used, steric repulsion between the ligands will reduce the ligand coverage of gold clusters. A well‐defined access granted gold nanocluster [Au23(Ph3P)10(dpa)2Cl](SO3CF3)2 (Au23, dpa=dipyridylamido) has been successfully synthesized. Single crystal structural determination reveals that Au23 has eight uncoordinated gold atoms in the shape of a distorted bicapped triangular prism. The accessibility of the exposed Au atoms has been confirmed quantitatively by luminescent titration with 2‐naphthalenethiol. This cluster has excellent performance toward selective oxidation of benzyl alcohol to benzaldehyde and demonstrates excellent stability due to the protection of negatively charged multidentate ligand dpa. [ABSTRACT FROM AUTHOR]

Gold nanoclusters with surface open sites are crucial for practical applications in catalysis. We have developed a surface geometric mismatch strategy by using mixed ligands of different type of hindrance. When bulky phosphine Ph3P and planar dipyridyl amine (Hdpa) are simultaneously used, steric repulsion between the ligands will reduce the ligand coverage of gold clusters. A well‐defined access granted gold nanocluster [Au23(Ph3P)10(dpa)2Cl](SO3CF3)2 (Au23, dpa=dipyridylamido) has been successfully synthesized. Single crystal structural determination reveals that Au23 has eight uncoordinated gold atoms in the shape of a distorted bicapped triangular prism. The accessibility of the exposed Au atoms has been confirmed quantitatively by luminescent titration with 2‐naphthalenethiol. This cluster has excellent performance toward selective oxidation of benzyl alcohol to benzaldehyde and demonstrates excellent stability due to the protection of negatively charged multidentate ligand dpa. [ABSTRACT FROM AUTHOR]

The identification of hydride(s) in gold nanoclusters is a challenging task, due to the instability of gold nanoclusters containing hydrides. Herein, we report two ultrastable hydrido gold nanoclusters protected by phosphine ligands: [Au20(PPh3)12H3](SbF6)3 (1H) and [Au20(PPh3)12H2(2-COOH-PhS)](PF6)3 (2H). The presence of hydrides in gold(0)–gold(I) nanoclusters is clearly demonstrated by ESI mass spectrometry and NMR spectroscopy. Single crystal structural determination reveals that both nanoclusters have an unprecedented Au20 core consisting of a Au9 unit and a Au11 unit. Such cores derived from the connection of different basic units are important for understanding the evolution and stability of metal nanoclusters. The hydride (H−) was also verified by a charge distribution calculation. [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]

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]

We report the total structure determination of a covalently bonded nanocluster polymer [Au7Ag9(dppf)3(CF3CO2)7BF4]n (1). This features a one-dimensional linear chain, consisting of unique molecular building blocks, Au7Ag8(dppf)3(CF3CO2)7 clusters, which are linked together by Ag–O bonds rather than Au–Au interactions or bidentate organic bridges as previously reported. [ABSTRACT FROM AUTHOR]

Two homoleptic alkynyl‐protected gold clusters with compositions of Na[Au25(C≡CAr)18] and (Ph4P)[Au25(C≡CAr)18] (Na⋅1 and Ph4P⋅1, Ar=3,5‐bis(trifluoromethyl)phenyl) were synthesized via a direct reduction method. 1 is a magic cluster analogous to [Au25(SR)18]− in terms of electron counts and metal‐to‐ligand ratio. Single‐crystal structure analysis reveals that 1 has an identical Au13 kernel to [Au25(SR)18]−, but adopts a distinctly different arrangement of the six peripheral dimer staple motifs. The steric hindrance of alkynyl ligands is responsible for the D3 arrangement of Au25. The introduction of alkynyl also significantly changes the optical absorption features of the nanocluster as supported by DFT calculations. This magic cluster confirms that there is a similar but quite different parallel alkynyl‐protected metal cluster universe in comparison to the thiolated one. Magic clusters Na[Au25(C≡CAr)18] and (Ph4P)[Au25(C≡CAr)18] (Ar=3,5‐bis(trifluoromethyl)phenyl) exhibit novel connection between staples and the Au13 core. Steric hindrance caused by rigid ligand coordination preference accounts for the different geometric and electronic structures. [ABSTRACT FROM AUTHOR]

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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]

Porous coordination cages with Zn, Ni and Co clusters exhibit different electronic structures dictating the evolution of reactive oxygen species, as reported by Hong-Cai Zhou, Yu Fang et al. in their Communication (e202303896). Keywords: Enzyme; Molecular Cage; Photocatalysis; Reactive Oxygen Species; Specificity EN Enzyme Molecular Cage Photocatalysis Reactive Oxygen Species Specificity 1 1 1 07/27/23 20230801 NES 230801 B Photocatalysts b . [Extracted from the article]

Keywords: Enzyme; Molecular Cage; Photocatalysis; Reactive Oxygen Species; Specificity EN Enzyme Molecular Cage Photocatalysis Reactive Oxygen Species Specificity 1 1 1 08/01/23 20230801 NES 230801 B Photocatalysts b . Porous coordination cages with Zn, Ni and Co clusters exhibit different electronic structures dictating the evolution of reactive oxygen species, as reported by Hong-Cai Zhou, Yu Fang et al. in their Communication (e202303896). Enzyme, Molecular Cage, Photocatalysis, Reactive Oxygen Species, Specificity. [Extracted from the article]

An alkynyl-protected gold nanocluster [Au40(PhC≡C)20(dppm)4](SbF6)4 (dppm = bis(diphenylphosphino)methane) (1) has been synthesized. Single-crystal X-ray diffraction reveals that the cluster has a face-centered cubic (FCC) Au34 kernel that is made up of two Au20 units via sharing a rectangular face. Two linear PhC≡C–Au–C≡CPh staple motifs are located around the central part of the Au34 core, and four L-shaped PhC≡C–Au–P^P staple motifs are located at the four corners of the Au34 core. Cluster 1 and [Au38(PhC≡C)20(PPh3)4](CF3SO3)2 both have the FCC Au34 core, and it is found that the diphosphine ligands bringing two more Au atoms into the system have significant effects on the optical properties and stability of the clusters. The combination of a diphosphine ligand and an alkynyl ligand is helpful in generating new 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]

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]

Gold(i) phosphinopyridyl clusters [Au9(PNC)6](BF4)3 (1) and [Au11(PNC)6(PPh3)2](BF4)5 (2) (PNC = 2-diphenylphosphinopyridyl monoion) are assembled. In contrast to the green luminescence of 1, 2 is brightly orange emissive in CH2Cl2, which shows the presence of unsupported AuI–AuI interactions in solution. Besides, 1 and 2 can selectively light up the mitochondria of living cells. [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]