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International audience; The first series of monocarboxylate-protected superatomic silver nanoclusters was synthesized and fully characterized by X-ray diffraction, fourier-transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), and electrospray ionization mass spectrometry (ESI-MS). Specifically, compounds [Ag(16)(L)(8)(9-AnCO(2))(12)](2+) (L = Ph(3)P (I), (4-ClPh)(3)P (II), (2-furyl)(3)P (III), and Ph(3)As (IV)) were prepared by a solvent-thermal method under alkaline conditions. These clusters exhibit a similar unprecedented structure containing a [Ag(8)@Ag(8)](6+) metal kernel, of which the 2-electron superatomic [Ag(8)](6+) inner core shows a flattened and puckered hexagonal bipyramid of S(6) symmetry. Density functional theory calculations provide a rationalization of the structure and stability of these 2-electron superatoms. Results indicate that the 2 superatomic electrons occupy a superatomic molecular orbital 1S that has a substantial localization on the top and bottom vertices of the bipyramid. The π systems of the anthracenyl groups, as well as the 1S HOMO, are significantly involved in the optical and photothermal behavior of the clusters. The four characterized nanoclusters show high photothermal conversion performance in sunlight. These results show that the unprecedented use of mono-carboxylates in the stabilization of Ag nanoclusters is possible, opening the door for the introduction of various functional groups on their cluster surface.

Accurately controlling the hydrolysis of metal ions can not only yield the desired structure of metal hydroxide clusters but also provide a deeper understanding of the formation process of natural hydroxide minerals. However, the capture of hydrolysis intermediates remains a significant challenge, and metal hydroxide clusters are mainly obtained by employing adventitious hydrolysis. In this study, we realized a hierarchical building block assembly from Y3+ ions to large Y12, Y34, and Y60 clusters by controlling the hydrolysis process of lanthanide ions under different pH conditions. Single-crystal structural analysis showed that the Y12 wheel, Y34 ship, and Y60 sodalite cage contain 4, 12, and 24 cubane-like [Y4(µ3-OH)4]8+ units, respectively. The structure of the Y60 cluster can be attributed to two Y34 clusters or six Y12 clusters linked by vertices. These clusters can be synthesized through the hydrolysis of Y3+ under different pH conditions, and Y60 can be prepared from the obtained Y12 or Y34 crystals by the simple addition of Y3+ ions. The capture and conversion of the intermediates of lanthanide series hydroxide clusters, Y12 or Y34, during the assembly from Y3+ ions to Y60 can facilitate an understanding of the formation process of high-nuclearity lanthanide clusters.

Based on the Venturi self-pumping effect, real-time sniffing with mass spectrometry (R-sniffing MS) is developed as a tool for direct and real-time mass spectrometric analysis of both gaseous and solid samples. It is capable of dual-mode operation in either gaseous or solid phase, with the corresponding techniques termed as R

In this work, rational design of highly soluble and phosphorescent Ag–Au cluster complexes with exceptional [2]catenane structures is conducted using 1,8-diethynyl-9H-carbazole (H3decz) as a rigid ...

Three face-centered-cubic (fcc) silver clusters-namely, [Ag14(LA)2(HLA)4(PPh3)8]2- (1), [Ag14(HLA)6(PPh3)8] (2), and [Ag14(NLA)6(PPh3)8] (3)-that are coprotected by lipoic acid (or its amide derivative) and phosphine ligands have been synthesized and structurally characterized (HLA = (±)-α-lipoic acid, LA = (±)-α-lipoate, and NLA = d,l-6,8-thioctamide). These clusters possess two superatomic electrons (the Jellium model), in harmony with a bonding octahedral Ag6 core capped with 8 Ag atoms. Alternatively, the metal framework of 1-3 can be described as adopting a face-centered cubic (fcc) structure elongated along one of the 3-fold axes. The 12 S atoms from the six bioligands bridge the 12 edges of the (fcc) cube, forming a distorted icosahedron. The counterions, solvent or guest molecules play an important role in dictating the crystal lattices of the products. This is the first report of atom-precise structures of Ag-lipoic acid (or its derivatives) clusters, paving the way for further study of structure-property relationships of these bioligand protected metal nanoclusters. Photoluminescence was observed for cluster 3 with complex temperature-dependent emission patterns and efficiencies.

Good aqueous dispersibility of metal chalcogenide nanoclusters with an atomically precise structure is desirable to achieve tiny and uniform cluster-based "quantum dots". However, there are big challenges toward this goal, especially for the large-sized nanoclusters without covalently bonded organic ligands, because the strong electrostatic interactions between closely packed negatively charged nanoclusters and protonated organic amine templates in the crystal lattice impede the dispersion of cluster-based bulk crystalline samples. Here, we report two iso-structured crystalline metal chalcogenides composed of discrete supertetrahedral T4-MInS nanoclusters with the formulas of [M

Most of polyoxometallates (POMs) templated silver nanoclusters recorded so far are polyoxomolybdates and polyoxotungstates; however, as congeneric polyoxochromates, they are rarely observed in silver nanoclusters. Herein, a high-nuclearity polyoxochromate, (CrIII4CrVI8O36)12-, is uncovered in a novel silver nanocluster (SD/Ag56a) as an anion template. The mixed-valent (CrIII4CrVI8O36)12- consists of four edge-sharing CrIIIO6 octahedra and eight CrVIO4 tetrahedra, which are fused together by sharing one or two vertexes. The (CrIII4CrVI8O36)12- is the by far highest nuclearity polyoxochromate and is trapped by outer Ag56 bracelet-like shell coprotected by quaternary ligands including iPrS-, NapCOO- (2-naphthalenecarboxylate), CF3COO-, and CH3CN. The antiferromagnetic property and solution behavior of SD/Ag56a are discussed in detail.

An alkynyl-protected gold nanocluster, Au22 (t BuC≡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 (t BuC≡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.

In the absence of inorganic anion templates and in high pH condition (pH ∼ 14), an unprecedented carbonate-hydrate supramolecule, [(CO3)2(H2O)]4−, trapped from atmospheric CO2, found to play an ani...

Thiacalix[4]arenes as a family of promising ligands have been widely used to construct polynuclear metal clusters, but scarcely employed in silver nanoclusters. Herein, an anion-templated Ag88 nanocluster (SD/Ag88a) built from p-tert-butylthiacalix[4]arene (H4TC4A) is reported. Single-crystal X-ray diffraction reveals that C4-symmetric SD/Ag88a resembles a metal-organic super calix comprised of eight TC4A4− as walls and 88 silver atoms as base, which can be deconstructed to eight [CrO4@Ag11(TC4A)(EtS)4(OAc)] secondary building units arranged in an annulus encircling a CrO42− in the center. Local and global anion template effects from chromates are individually manifested in SD/Ag88a. The solution stability and hierarchical assembly mechanism of SD/Ag88a are studied by using electrospray mass spectrometry. The Ag88 nanocluster represents the highest nuclearity metal cluster capped by TC4A4−. This work not only exemplify the specific macrocyclic effects of TC4A4− in the construction of silver nanocluster but also realize the shape heredity of TC4A4− to overall silver super calix., The assembly of giant silver clusters by using macrocylic multidentate ligand remains a challenge. Here, the authors synthesize a chromate-templated 88-nuclei silver super calix and reveal the role of anion templating effects and a hierarchical assembly mechanism.

The combination of CrO42− anion and N , N ′-dimethylformamide (DMF)-containing solvent helps to stabilize an atom-precise ultrasmall Ag6 kernel into a 52-nuclei silver shell, giving a core-shell Ag6@Ag52 wheel-like structure ( SD/Ag58b ). The solution behavior and photocurrent response property were investigated in details.

Accurately controlling the hydrolysis of metal ions can not only yield the desired structure of metal hydroxide clusters but also provide a deeper understanding of the formation process of natural hydroxide minerals. However, the capture of hydrolysis intermediates remains a significant challenge, and metal hydroxide clusters are mainly obtained by employing adventitious hydrolysis. In this study, we realized a hierarchical building block assembly from Y

Constructing supramolecular cages with multiple subunits via weak intermolecular interactions is a long-standing challenge in chemistry. So far, π-stacked supramolecular cages still remain unexplored. Here, we report a series of π-stacked cage based hierarchical self-assemblies. The π-stacked cage (π-MX-cage) is assembled from 16 [MXL]+ ions (M = Mn2+, Co2+; X = Br-, SCN-, Cl-; and L = tris(2-benzimidazolylmethyl)amine) via 18 intermolecular π-stacking interactions. The tetrahedral cage, consisting of four [MXL]+ ions as the vertexes and six pairs of [MXL]+ ions as the edges, features 48 exterior N-H hydrogen bond donors for hydrogen bond formation with guest molecules. By variation of the M2+/X- pair, the π-MX-cage demonstrates unique versatility for incorporating a wide variety of species via different hydrogen-bonding modes during the assembly of hierarchical superstructures. In specific, the π-MnBr-cages encapsulate acetonitrile (CH3CN) or cis-1,3,5-cyclohexanetricarbonitrile (cis-HTN) molecules in the central voids, while a core-shell tetrahedral inorganic cluster [Mn(H2O)6]@([Mn(H2O)4]4[Br42-]6) (Mn@Mn4-cage) is captured within the interstitial regions between cages. The π-CoSCN-cages are capable of stabilizing reactive sulfur-containing species, such as S2O42-, S2O62-, and HSO3- ions, in the hierarchical superstructure. Finally, H2PO4- ions are incorporated between π-CoCl-cages, resulting in an inorganic mesoporous framework. These results provide insights into further exploring the chemistry and hierarchical assembly of supramolecular cages based on π-π stacking intermolecular interactions.

A mixed-valent hexadecanuclear manganese cluster, [MnII2MnIII14(trz)14(thetach)4(μ3-O)8(H2O)10](ClO4)6 (Mn16), containing two MnII and 14 MnIII ions, is constructed from mixed in situ generated ligands, 1,2,3-triazole (Htrz) and 1,3,5-tri(2-hydroxyethyl)-1,3,5-triazacyclohexane (H3thetach). Remarkably, both ligands were not initially added into the reaction system, and their formations involve the in situ ligand decomposition and subsequent condensation reactions. The core of Mn16 is an elongated torus comprised of eight Mn atoms and four [Mn2O2] subunits bridged by oxo or alkoxide. The high-resolution electrospray ionization mass spectrometry (HR-ESI-MS) of Mn16 dissolved in CH3CN indicates its structure remains intact as +3 and +4 species. Temperature and field dependent magnetization revealed predominantly antiferromagnetic exchange interactions within the cluster. The work provides one-pot synthesis of high-nuclearity manganese clusters using the ligands generated by in situ reactions in a tandem fashion.

Control over core structure is much more challenging than that over shell structure in core–shell silver nanoclusters. Herein, two isostructural chalcogen-mediated [Ag6Z4@Ag36] (Z = S or Se) nanocl...

Although great achievements have been made in the synthesis of giant lanthanide clusters, novel structural models are still scarce. Herein, we report a giant lanthanide cluster Dy76 , constructed from [Dy3 (μ3 -OH)4 ] and [Dy5 (μ4 -O)(μ3 -OH)8 ] building blocks. As the largest known Dy cluster, the structure of Dy76 can be seen as arising from the fusion of two Dy48 clusters; these clusters can be isolated under various synthetic conditions and were characterized by single-crystal X-ray diffraction. This new, fused structural model of the pillar motif has not been found in Ln clusters. Furthermore, the successful conversion of Dy76 back into Dy48 in a retrosynthetic manner supports the proposed fusion formation mechanism of Dy76 . Electrospray ionization mass spectrometry (ESI-MS) analysis suggests that the metal cluster skeleton of Dy76 shows good stability in various solvents. This work not only reveals a new structural type of Ln clusters but also provides insight into the novel fusion assembly process.

Two novel space craft-like octanuclear Co(II)-silsesquioxane nanocages, {Co8[(MeSiO2)4]2(dmpz)8} (SD/Co8a) and {Co8[(PhSiO2)4]2(dmpz)8} (SD/Co8b) (SD = SunDi; Hdmpz = 3,5-dimethylpyrazole), have been constructed from two similar multidentate silsesquioxane ligands assisted with a pyrazole ligand. The Co8 skeleton consists of eight tetrahedral Co(II) ions arranged in a ring and is further capped by two (MeSiO2)4 ligands up and down. The auxiliary dmpz- ligands seal the ring finally. Electrospray ionization mass spectrometry revealed SD/Co8a and SD/Co8b are highly stable in CH2Cl2. Magnetic analysis implies that SD/Co8a announces antiferromagnetic interactions between Co(II) ions. Moreover, both of them display good homogeneous catalytic activity for hydroboration of ketones in the presence of pinacolborane under mild conditions.

The search for functional materials, for example those aiming at microelectronics, magnetic recording, and catalysis, often ventures into mixed metal systems to achieve optimization of the properti...

The elaborate selection of capping ligands is of great importance in the synthesis of atomically precise metal nanoclusters. Organic thiolates, alkynyls, phosphines, and/or their combinations are the ligands most widely utilized to protect metal nanoclusters, while inorganic oxo anions have been almost neglected in this field. Herein, the first CrO42–/tBuC≡C– co-capped Ag48 nanocluster (SD/Ag48, SD = SunDi) was synthesized and structurally characterized by single-crystal X-ray diffraction. The pseudo-5-fold symmetric metal skeleton of SD/Ag48 shows a core–shell structure composed of a Ag23 cylinder encircled by an outer Ag25 shell. Unprecedentedly, coexistence of inorganic (CrO42–) and organic (tBuC≡C–) ligands was observed on the surface of SD/Ag48. The inorganic CrO42– anion plays three important roles in the construction of silver nanoclusters: (i) passivating the Ag23 kernel; (ii) connecting the core and shell; and (iii) protecting the Ag25 shell. This nanocluster belongs to a 14e superatom system and...

A diphosphine-protected 18-gold-atom nanocluster was isolated via a facile reduction of an AuI precursor by NaBH4. Its composition was identified as {[Au18(dppm)6Cl4]·C6H6·3Cl·PF6} (SD/Au18, SD = SunDi; dppm = bis-(diphenylphosphino)methane) by X-ray single crystal structural analysis. This nanocluster possesses a prolate shape and is built from an Au10 kernel (bi-octahedral Au6 units sharing one edge) fused with two Au7 caps via sharing six gold atoms. The identity of the Au18 cluster is further demonstrated by ESI-MS. The number of valence electrons of [Au18(dppm)6Cl4]4+ is 10 (n* = 18-4-4), which does not match with the known magic numbers according to the spherical jellium model, and elongated models must be considered. The special stability of the Au18 cluster likely arises from geometrical factors in the metallic core. Two charge states are reported for this system. This work not only presents the structure elucidation of a diphosphine-protected Au18 nanocluster, but also provides an important insight into the growth pattern of gold nanoclusters and the charge states they can achieve.

Fruitful efforts have been made for the assembly of nanosized silver clusters, and the majority of which are protected by thiolates and alkynyl ligands. By comparison, the reported silver clusters or silver-cluster-based supramolecular networks protected by N-donor ligands are very rare because of the hard basicity of N-donor ligands with respect to the soft acid Ag(I). Here, by using an N-donor ligand, a 2D Cl@Ag11N24-based supramolecular network [Cl@Ag11(L)8X2 ]n (X = CF3COO− for 1, NO3− for 2 and CF3SO3− for 3) has been constructed with a Ag–O bond as the linker. This high-nuclearity silver cluster Cl@Ag11N24 has an open dendritic structure with a high coordination ratio of the N atom, which is different from the well-established macrocycle, spheroidal cage and core–shell architectures based on silver–thiolate/alkynyl/phosphine clusters. The stability and assembly process of the 2D network has been studied by high-resolution electrospray mass spectrometry (HR-ESI-MS). Notably, 1 shows an intriguing dual-emission feature that is strongly influenced by different excitation wavelengths and temperatures. Significantly, this work sheds new light on the construction of novel silver clusters and supramolecular networks based on them and provides a kind of luminescent material.

An ab initio one-pot synthesis of the bimetallic clusters [AunAg44–n(SC6H3F2)30]4– (abbreviated (AuAg)44; n ≤ 12) is reported. The mixed-metal (AuAg)44 clusters, synthesized with different reactant...

In this work, rational design of highly soluble and phosphorescent Ag-Au cluster complexes with exceptional [2]catenane structures is conducted using 1,8-diethynyl-9

The assembly of gigantic heterometallic metal clusters remains a great challenge for synthetic chemistry. Herein, based on the slow release strategy of lanthanide ions and in situ formation of lacunary polyoxometalates, two giant 3d-4f polyoxometalate inorganic clusters [LaNi

Three face-centered-cubic (fcc) silver clusters-namely, [Ag

Gaseous compounds are usually on-line detectable on sensors. The limitations of conventional sensors are suffering from incapability for exactly identifying multiple components as well as incompatibility to possible toxicants in every odor sample. Herein, we discuss an inlet modification to the laboratory standard mass spectrometer, inspired by the sensitive olfactory systems of animals, for direct sniffing, established by connecting a mini pump to the nebulizer gas tubing. The modified mass spectrometry method-sniffing-mass spectrometry (sniffing-MS)-can acquire detailed fingerprint spectra of mixed odors and shows high tolerance to toxicants. Furthermore, the method has a low limit of detection in the order of parts per trillion and is a sampling-free technique for analyzing various gaseous compounds simultaneously, thus offering versatility for smelling daily commodities, tracking diffusion, and locating position of odors. Sniffing-MS can mimic or even surpass the olfaction of animals and is applicable for analyzing gaseous/volatile compounds, especially those polar compounds, in a simple manner depending on the intrinsic molecular mass-to-charge ratio.

The largest known polyoxometalate (POM)-templated silver-alkynyl cluster, [(EuW10 O36 )2 @Ag72 (tBuC≡C)48 Cl2 ⋅4 BF4 ] (SD/Ag20), was isolated under solvothermal conditions and structurally characterized. It was confirmed by single-crystal X-ray diffraction (SCXRD) as a {EuW10 }2 -in-{Ag72 } clusters-in-cluster rod-like compound. The high-resolution electrospray ionization mass spectrometry (HR-ESI-MS) shows that such a double anion-templated cluster is assembled from a crucial single anion-templated Ag42 intermediate in the solution. The crystallization of Ag42 species (SD/Ag21), followed by SCXRD, gave an important clue about the assembly route of SD/Ag20 in solution: the Ag42 cluster eliminates six silver atoms laterally, then fuses together at the vacant face to form the final Ag72 cluster (elimination-fusion mechanism). The characteristic emission of [EuW10 O36 ]9- is well maintained in SD/Ag20. This work not only provides a new method for the synthesis of larger silver clusters as well as the functional integration of the silver cluster and POMs, but also gives deep insights about the high-nuclear silver cluster assembly mechanism.

A 90-nucleus silver cluster (SD/Ag38) cocapped by tBuC6H4S- and PhCOO- ligands was synthesized using hetero-anion template method. Single-crystal X-ray diffraction (SCXRD) revealed a 90-nucleus metallic dumbbell-like core constructed by two large W5O19@Ag38 heads sandwiching one slender (SO4)2@Ag14 waist. Both W5O198- and SO42- templates were in situ generated and synergistically induced the formation of the largest known anion-templated silver cluster. Although SD/Ag38 is emission-silent at room temperature, increasingly brighter near-infrared (NIR) emission at ca. 742 nm was detected on cooling from 293 to 93 K.

Both the electronic and surface structures of metal nanomaterials play critical roles in determining their chemical properties. However, the non-molecular nature of conventional nanoparticles makes it extremely challenging to understand the molecular mechanism behind many of their unique electronic and surface properties. In this work, we report the synthesis, molecular and electronic structures of an atomically precise nanoparticle, [Ag206L72]q (L = thiolate, halide; q = charge). With a four-shell Ag7@Ag32@Ag77@Ag90 Ino-decahedral structure having a nearly perfect D5h symmetry, the metal core of the nanoparticle is co-stabilized by 68 thiolate and 4 halide ligands. Both electrochemistry and plasmonic absorption reveal the metallic nature of the nanoparticles, which is explained by density functional theory calculations. Electronically, the nanoparticle can be considered as a superatom, just short of a major electron shell closing of 138 electrons (q = –4). More importantly, many of ligands capping on the nanoparticle are labile due to their low-coordination modes, leading to high surface reactivity for catalysing the synthesis of indoles from 2-ethynylaniline derivatives. The results exemplify the power of the atomic-precision nanocluster approach to catalysis in probing reaction mechanisms and in revealing the interplay of heterogeneous reactivities, electronic and surface structural dynamics, thereby providing ways for optimization.

A novel nonanuclear copper(II) nanocluster (Cu9) was constructed from a well-designed multidentate pyrazole–alcohol ligand and using various small anions. The Cu9 skeleton was found to consist of two similar Cu5 cluster units sharing one central CuII ion and to be protected by the outer organic ligand and auxiliary small anions. The solution behavior of Cu9 was studied in detail by applying the ESI-MS technique. Magnetism analysis implied the presence of antiferromagnetic interactions between the CuII ions.

A discrete 78-nucleus silver–sulfur nanocluster with a sulfate-centered multishell structure was isolated and characterized. Its crystal structure revealed 18 and 60 Ag atoms in the inner and outer shell, respectively. The inner shell of 18-nuclearity Ag atoms is a very rare convex polyhedron featuring an elongated triangular orthobicupola. The incorporation of a sulfate anion and multishell arrangement in the nanocluster led to a dramatic decrease in the band gap (Eg = 1.40 eV). Our study showed that simple anions can also induce the formation of high-nuclearity silver clusters with excellent optical properties.

The synthesis of Group 11 metal chalcogenide supertetrahedral clusters (SCs) still remains a great challenge mainly due to the high tendency of metal aggregation through metallophilicity and global charge balance. Demonstrated herein are the preparation, crystallographic characterization, and optical properties of two stable silver-sulfur SCs through ligand-control; one as a discrete zero-dimensional (0D) V3,4-type cluster and the other as a one-dimensional (1D) zigzag chain extended by alternating V3,2-type clusters. The notation Vn,m (where n is the number of metal layers, and m is the number of vacant corners) is used to describe a new series of vacant-corner SCs, which can be derived from the regular Tn clusters. The existence of vacant-corner-type SCs may be ascribed to the low valence and tri-coordinated environment of silver ions. These are the first representatives of structurally determined silver-sulfur tetrahedral clusters thus far. This work enriches the coinage-metal chalcogenide tetrahedral cluster portfolio, discovers vacant-corner SCs present in silver-sulfur hybrid tetrahedral clusters, and provides effective means for further development of Group 11 coinage-metal chalcogenide SCs.

Postsynthetic decoration of the Mn7, {MnIII⊂MnII6}, core with CdII in the outer shell to form the next generation Mn13Cd6, {MnIII⊂MnIII3MnII3⊂ MnII6CdII6}, core–shell disc was achieved and confirmed by single-crystal X-ray diffraction. The formation of Mn13Cd6 has only been successful with CdII and if the Cd salt is added within the first half hour window when the inner Mn7 has formed. EDX and ICP-AES gave the accurate content and confirm the average found by X-ray diffraction. HR-ESI-MS was even more precise by revealing three prominent molecular species, Mn13Cd6, Mn14Cd5 and Mn15Cd4, having a distribution of metals. The presence of nonmagnetic metal on the periphery reduces the exchange between these clusters as well as the low magnetic moment decreases the dipolar interaction resulting in a paramagnet compared to the ferrimagnetism found for the parent Mn19, {MnIII⊂MnIII3MnII3⊂MnII12}, disc. This study opens the way for the syntheses of heterometallic core–shell clusters in a controllable fashion.

Surface ligands play important roles in controlling the size and shape of metal nanoparticles and their surface properties. In this work, we demonstrate that the use of bulky thiolate ligands, along with halides, as the surface capping agent promotes the formation of plasmonic multiple-twinned Ag nanoparticles with high surface reactivities. The title nanocluster [Ag141X12(S-Adm)40]3+ (where X = Cl, Br, I; S-Adm = 1-adamantanethiolate) has a multiple-shell structure with an Ag71 core protected by a shell of Ag70X12(S-Adm)40. The Ag71 core can be considered as 20 frequency-two Ag10 tetrahedra fused together with a dislocation that resembles multiple-twinning in nanoparticles. The nanocluster has a strong plasmonic absorption band at 460 nm. Because of the bulkiness of S-Adm, the nanocluster has a low surface thiolate coverage and thus unusually high surface reactivities toward exchange reactions with different ligands, including halides, phenylacetylene and thiols. The cluster can be made water-soluble by ...

Two novel POM-based inorganic–organic hybrids, [Cu6II(2,2′-bipy)6(Mo6O22)(SiW12O40)]n (1), and {[Cu6II(ppz)6(H2O)5(MoO4)(SiW12O40)]·4H2O}n (2) (2,2′-bipy = 2,2′-bipyridine, Hppz = 3-(pyrid-2-yl)pyrazole), have been constructed from heteropolytungstates and molybdates. Two compounds have been identified by single crystal X-ray diffraction, elemental analysis, and FT-IR. Compound 1 shows a 1D (one-dimensional) chain structure constructed from classical Keggin heteropolytungstate [SiW12O40]4– clusters and [Cu6(2,2′-bipy)6] modified isopolymolybdates [Mo6O22]8–. Compound 2 also represents a 1D chain-like motif built from classical Keggin heteropolytungstate [SiW12O40]4– clusters and [Cu8(ppz)6(H2O)5] modified molybdates MoO42–. Compound 1 represents the first example of POM-based inorganic–organic hybrid with mixed heteropolytungstates and isopolymolybdates. ESI-MS (electrospray ionization mass spectrometry) technique was employed to reveal the species and their evolutions in the hydrothermal reaction, whereb...

Inspired by the transition-metal-oxo cubical Mn4CaO5 in photosystem II, we herein report a disc-like heptanuclear mixed-valent cobalt cluster, [CoII5CoIII2(mdea)4(N3)2(CH3CN)6(OH)2(H2O)2·4ClO4] (1, H2mdea = N-methyldiethanolamine), for photocatalytic oxygen evolution. The topology of the Co7 core resembles a small piece of cobaltate protected by terminal H2O, N3–, CH3CN, and multidentate N-methyldiethanolamine at the periphery. Under the optimal photocatalytic conditions, 1 exhibits water oxidation activity with a turnover number (TON) of 210 and a turnover frequency (TOFinitial) of 0.23 s–1. Importantly, electrospray mass spectrometry (ESI-MS) was used to not only identify the possible main active species in the water oxidation reaction but also monitor the evolutions of oxidation states of cobalt during the photocatalytic reactions. These results shed light on the design concept of new water oxidation catalysts and mechanism-related issues such as the key active intermediate and oxidation state evolutio...