Supracluster Assembly of Archimedean Cages with 72 Hydrogen Bonds for the Aldol Addition Reaction.

Clusters that can be experimentally precisely characterized and theoretically accurately calculated are essential to understanding the relationship between material structure and function. Here, we propose the concept of "supraclusters", which aim to connect "supramolecules" and "suprananoparticles" as well as reveal the unique assembly behavior of "supraclusters" with nanoparticle size at the molecular level. The implementation of supraclusters is full of challenges due to the difficulty in satisfying the ordered connectivity of clusters due to their abundant and dispersed hydrogen bonding sites. By solvothermal synthesis under a high catechol (H2 CATs) content, we successfully isolated a series of triangular {Al6 M3 } cluster compounds possessing brucite-like structural features. Interestingly, eight {Al6 M3 } clusters form 72-fold strong hydrogen bonding truncatedhexahedron Archimedean {Al6 M3 }8 supracluster cage (abbreviated as H-tcu). Surprisingly, the solution stability of the H-tcu was further proved by electrospray ionization mass spectrometry (ESI-MS) characterization. Therefore, it is not difficult to explain the reason for assembly of H-tcu into edge-directed and vertex-directed isomers. These porous supraclusters can be obtained by scale-up synthesis and exhibit a noticeable catalysis effect towards the condensation of acetone and p-nitrobenzaldehyde. As an intermediate state of supramolecule and suprananoparticle, the supracluster assembly can enrich the cluster chemistry and bring new structural types.

Real-Time Sniffing Mass Spectrometry Aided by Venturi Self-Pumping Applicable to Gaseous and Solid Surface Analysis.

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 Rg-sniffing MS and Rs-sniffing MS, respectively. In its gaseous mode, Rg-sniffing MS is capable of analyzing a gaseous mixture with response time (0.8-2.1 s rise time and 7.3-9.6 s fall time), spatial resolution (<80 µm), three-dimensional diffusion imaging, and aroma distribution imaging of red pepper. In its solid mode, an appropriate solvent droplet desorbs the sample from a solid surface, followed by the aspiration of the mixture using the Venturi self-pumping effect into the mass spectrometer, wherein it is ionized by a standard ion source. Compared with the desorption electrospray ionization (DESI) technique, Rs-sniffing MS demonstrated considerably improved limit of detection (LOD) values for arginine (0.07 µg/cm2 Rs-sniffing vs 1.47 µg/cm2 DESI), thymopentin (0.10 µg/cm2 vs 2.67 µg/cm2), and bacitracin (0.16 µg/cm2 vs 2.28 µg/cm2). Rs-sniffing is applicable for the detection of C60(OCH3)6Cl-, an intermediate in the methoxylation reaction involving C60Cl6 (solid) and methanol (liquid). The convenient and highly sensitive R-sniffing MS has a characteristic separation of desorption from the ionization process, in which the matrix atmosphere of desorption can be interfaced by a pipe channel and self-pumped by the Venturi effect with consequent integration using a standard ion source. The R-sniffing MS operates in a voltage-, heat-, and vibration-free environment, wherein the analyte is ionized by a standard ion source. Consequently, a wide range of samples can be analyzed simultaneously by the R-sniffing MS technique, regardless of their physical state.

Constructing π-Stacked Supramolecular Cage Based Hierarchical Self-Assemblies via π···π Stacking and Hydrogen Bonding.

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.

Hydrolysis-Promoted Building Block Assembly: Structure Transformation from Y12 Wheel and Y34 Ship to Y60 Cage.

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.

Synthesis, Structures, and Photoluminescence of Elongated Face-Centered-Cubic Ag14 Clusters Containing Lipoic Acid and Its Amide Analogue.

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.

A Polyoxochromate Templated 56-Nuclei Silver Nanocluster.

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.

Assembly of silver Trigons into a buckyball-like Ag180 nanocage.

Buckminsterfullerene (C60) represents a perfect combination of geometry and molecular structural chemistry. It has inspired many creative ideas for building fullerene-like nanopolyhedra. These include other fullerenes, virus capsids, polyhedra based on DNA, and synthetic polynuclear metal clusters and cages. Indeed, the regular organization of large numbers of metal atoms into one highly complex structure remains one of the foremost challenges in supramolecular chemistry. Here we describe the design, synthesis, and characterization of a Ag180 nanocage with 180 Ag atoms as 4-valent vertices (V), 360 edges (E), and 182 faces (F)--sixty 3-gons, ninety 4-gons, twelve 5-gons, and twenty 6-gons--in agreement with Euler's rule V - E + F = 2. If each 3-gon (or silver Trigon) were replaced with a carbon atom linked by edges along the 4-gons, the result would be like C60, topologically a truncated icosahedron, an Archimedean solid with icosahedral (Ih) point-group symmetry. If C60 can be described mathematically as a curling up of a 6.6.6 Platonic tiling, the Ag180 cage can be described as a curling up of a 3.4.6.4 Archimedean tiling. High-resolution electrospray ionization mass spectrometry reveals that {Ag3}n subunits coexist with the Ag180 species in the assembly system before the final crystallization of Ag180, suggesting that the silver Trigon is the smallest building block in assembly of the final cage. Thus, we assign the underlying growth mechanism of Ag180 to the Silver-Trigon Assembly Road (STAR), an assembly path that might be further employed to fabricate larger, elegant silver cages.

Structure Determination of Alkynyl-Protected Gold Nanocluster Au22 (t BuC≡C)18 and Its Thermochromic Luminescence.

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.

[Ag48(C≡C tBu)20(CrO4)7]: An Atomically Precise Silver Nanocluster Co-protected by Inorganic and Organic Ligands.

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 exhibits successive molecule-like absorption bands from the visible to the ultraviolet region. This work not only establishes a fresh inorganic ligand strategy in the synthesis of silver nanoclusters but also provides a new insight into the important surface coordination chemistry of CrO42- in the shape control of silver nanoclusters.

Chalcogens-Induced Ag6Z4@Ag36 (Z = S or Se) Core-Shell Nanoclusters: Enlarged Tetrahedral Core and Homochiral Crystallization.

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) nanoclusters (SD/Ag42a and SD/Ag42b) caging tetrahedral [Ag6Z4] as cores were synthesized by introducing Ph3CSH or Ph3PSe as slow-release source of S2- or Se2-, respectively, and characterized by single-crystal X-ray diffraction (SCXRD). As compared to the previously reported [AgS4@Ag36] cluster (Ag37), we found that introducing additional S2- or Se2- ions can effectively enlarge the inner core from tetrahedral AgS4 to Ag6Z4, which is a regular octahedron of silver with four Z2- capping on one tetrahedral set of four faces. More interestingly, the molecular enantiomers of SD/Ag42a and SD/Ag42b segregate into different crystals (P212121), while those of Ag37 form racemic crystals (I41/acd). The larger Ag6Z4 core in Ag42 clusters also extends their emission to the near-infrared region (∼760 nm). The study confirms that chalcogenide can enlarge the nuclearity of nanoclusters by altering the inner core structure and affords a new strategy to synthesize chiral core-shell silver nanoclusters of higher-order in controlled fashion.

Hexadecanuclear MnII2MnIII14 Molecular Torus Built from in Situ Tandem Ligand Transformations.

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.

Space Craft-like Octanuclear Co(II)-Silsesquioxane Nanocages: Synthesis, Structure, Magnetic Properties, Solution Behavior, and Catalytic Activity for Hydroboration of Ketones.

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.

Self-Organization into Preferred Sites by MgII, MnII, and MnIII in Brucite-Structured M19 Cluster.

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 properties. Thus, understanding site preference and self-organization is crucial but hard to implement. Herein, we present a system whereby MgII, MnII, and MnIII ions selectively locate exact positions within the Brucite-structured cluster, Mn13Mg6, [MnIII⊂MgII6⊂MnII9MnIII3( L)18(OH)12(N3)6](ClO4)6·12CH3CN, H L = 1-(hydroxymethyl)-3,5-dimethylpyrazolate). The MnIII being small (78 pm) takes up the core position; while 6 MgII (86 pm) are located in the inner ring, and the 9 large MnII (97 pm) and 3 MnIII occupy the outer ring. The factors (a) ionic radii, (b) regularity in coordination geometry, oxophilicity, and softness of MgII compared to MnII, and (c) Jahn-Teller distortion of MnIII may all be implicated synergistically. Electrospray ionization mass spectrometry reveals the M19 disc remains an integral unit when crystals are dissolved, and exchange between Mg and Mn occurs within the disc during its formation. Diamagnetic MgII doping insulates the magnetic exchange between the central MnIII and those in the outer ring, thus giving an overall antiferromagnetic exchange interaction between nearest-neighbors of the outer ring. The work reveals the underlying rule for site-preference of main group metal versus transition metal in disc-like Brucite-structured cluster and provides an elegant new avenue to assemble heterometallic clusters in a stepwise fashion.

A Giant Dy76 Cluster: A Fused Bi-Nanopillar Structural Model for Lanthanide Clusters.

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.

Anisotropic Assembly of Ag52 and Ag76 Nanoclusters.

Although there has been an upsurge of interest in anisotropic assembly of inorganic nanoparticles, atomically precise self-assembly of anisotropic metal clusters is extremely rare. Herein, we presented two novel silver nanoclusters, Ag52 (SD/Ag23) and Ag76 (SD/Ag24), which are interiorly templated by five MoO42- and a pair of Mo6O228- anions, respectively, and coprotected by bridging RSH and terminal diphosphine ligands exteriorly. Regiospecific distribution diphosphine ligands on the surface and the arrangement of multiple molybdate templates within the nanoclusters synergetically tailor their shapes to anisotropic oblate spheroid and elongated rod, respectively. This work not only open up new avenues for the synthesis of silver nanoclusters with novel metal skeleton shapes and anisotropic surface structures but also give important insights for the anisotropic growth of silver nanoclusters through surface modifications or/and template organizations.

Johnson Solids: Anion-Templated Silver Thiolate Clusters Capped by Sulfonate.

Sulfonates were incorporated into six novel high-nuclearity silver(I) thiolate clusters under the guidance of anion templates varied from S2- , SO42- , α-[Mo5 O18 ]6- , ß-[Mo5 O18 ]6- , [Mo2 O8 ]4- , to [Mo4 O14 (SO4 )]6- . Single crystal X-ray analysis revealed that SD/Ag1, SD/Ag3, SD/Ag5, and SD/Ag6 are discrete [S@Ag60 ], [α-Mo5 O18 @Ag36 ], [Mo2 O8 @Ag30 ]2 , and [Mo4 O14 (SO4 )@Ag73 ] clusters, respectively, whereas SD/Ag2 and SD/Ag4 are one-dimensional (1D) chains based on the [SO4 @Ag20 ] and [ß-Mo5 O18 @Ag36 ] cluster subunits, respectively. Their silver skeletons are protected exteriorly by thiolates and sulfonates and interiorly supported by diverse anions as templates. Structurally, cluster SD/Ag1 is a typical core-shell structure comprised of an inner Ag12 cuboctahedron and an outer Ag48 shell. The sulfate-templated drum-like Ag20 cluster subunits are bridged by PhSO3- to give a 1D chain of SD/Ag2. Complex SD/Ag3 and SD/Ag4 are spindle-like Ag36 clusters with isomeric [Mo5 O18 ]6- inside, and the latter is further extended to a 1D chain through PhSO3- bridges. A pair of [Mo2 O8 ]4- templated gourd-like Ag30 clusters are dimerized in a head-to-head fashion to form SD/Ag5. Complex SD/Ag6 is the largest cluster in this family and doubly templated by unprecedented [Mo4 O14 (SO4 )]6- anions. Geometrically, the silver shells of SD/Ag1-SD/Ag5 show the polyhedral features of Johnson solids, instead of the usual Platonic or Archimedean solids. Solution behaviors and luminescent properties were also investigated in detail.

Three Silver Nests Capped by Thiolate/Phenylphosphonate.

Introducing phenylphosphonic acid (H2 PPA) into the Ag/tBuSH assembly system has produced a family of nanoscale-sized, high-atom number, silver thiolate/PPA nests (SD/Ag45 a, SD/Ag66 a, and SD/Ag73 a) with impressive core-shell features. SD/Ag45 a is a 45-atom ellipsoid comprised of an Ag36 shell trapping an Ag9 S2 three-bladed rotor inside. SD/Ag66 a comprises an inner rod-like Ag20 core and an outer Ag44 shell, giving a 64-atom nest. These Ag64 nests are further extended by Ag(CN)2 linkers to form a one-dimensional chain structure. SD/Ag73 a is a three-shell 73-nucleus silver nest with a central silver atom enclosed in a rhombicuboctahedron of 24 silver atoms, which is itself enclosed in the outermost shell of a rectified version of a 48-Ag octahedral Goldberg 2,0 cage. The solution behaviors and optical absorption properties of the three nests are described in detail. Of note, SD/Ag45 a and SD/Ag73 a emit in the near-infrared region and show different luminescent thermochromic behavior. This work demonstrates that the participation of H2 PPA strongly influences the structures of silver thiolate nests, thus providing a new route to fabricate and modify them in a more rational way.

Elimination-Fusion Self-Assembly of a Nanometer-Scale 72-Nucleus Silver Cluster Caging a Pair of [EuW10 O36 ]9- Polyoxometalates.

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.

Core-Shell {Mn7⊂(Mn,Cd)12} Assembled from Core {Mn7} Disc.

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.

Silver-Sulfur Hybrid Supertetrahedral Clusters: The Hitherto Missing Members in the Metal-Chalcogenide Tetrahedral Clusters.

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.