Silver Thiolate Nano‐sized Molecular Clusters and Their Supramolecular Covalent Frameworks: An Approach Toward Pre‐templated Synthesis

A series of seven new complexes including silver‐thiolate molecular clusters and their covalent supramolecular frameworks have been assembled from the silver carbide precursor Ag₂C₂ using a C₂²⁻ pre‐templated approach. Herein, two prototype clusters Ag₁₄(SR)₆ and CO₃@Ag_m (SR)₁₀ (R=isopropyl, cyclohexyl or tert ‐butyl; m= 18 or 20) are employed to construct cluster‐based metal–organic frameworks of different dimensions. In particular, both new ellipsoidal tetradecanuclear molecular cluster compounds, namely, Ag₁₄(S‐i Pr)₆(CO₂CF₃)₈⋅(DMSO)₆ (two polymorphic forms 1 , 2 ) and [Ag₁₄(S‐Cy)₆(CO₂CF₃)₈(DMSO)₄]⋅(DMSO)₃ ( 3 ), and a cluster‐based metal–organic framework {Ag₃[Ag₁₄(S‐i Pr)₆(CO₂CF₃)₁₁(H₂O)₃CH₃OH]⋅(H₂O)_2.5}_n ( 4 ) have been isolated and structurally characterized. Furthermore, increased acidity of the reaction mixture afforded three carboxylate‐templated cluster based frameworks: a chain‐like compound {[HN(CH₃)₂CO]⋅[CO₃@Ag₁₈(S‐t Bu)₁₀(NO₃)₇(DMF)₄]⋅DMF}_n ( 5 ), as well as two layer‐type compounds, namely, {Ag[CO₃@Ag₂₀(S‐i Pr)₁₀(CO₂CF₃)₉(CO₂HCF₃)(CH₃OH)₂]}_n ( 6 ) and {Ag₂[CO₃@Ag₂₀(S‐Cy)₁₀(CO₂CF₃)₁₀(CO₂HCF₃)₂(H₂O)₂]⋅(H₂O)₃⋅(CH₃OH)₃}_n ( 7 ) exhibiting sql ‐net characteristics. It is demonstrated that the C≡C²⁻ pre‐template, which draws several Ag⁺ ions together to form the C₂@Ag_n entity, plays an indispensable role in the syntheses of these compounds. Furthermore, covalent linkage of these nano‐sized silver thiolate clusters from one‐ to three‐dimensions revealed enormous potential for the future development of silver cluster‐based frameworks.     

High‐Nuclearity Silver Thiolate Clusters Constructed with Phosphonates

The n‐butylphosphonate ligand has been employed to construct three new silver(I) thiolate compounds. Single‐crystal X‐ray analysis revealed that complexes 1 and 2 are Ag₄₈ and Ag₅₁ coordination chain polymers, while 3 contains a discrete Ag₄₈ cluster, in which three different kinds of silver(I) thiolate cluster shells enclose three different phosphonate‐functionalized silver(I) cluster cores, respectively. The structures of clusters in 1 – 3 feature three three‐shell arrangements, S@Ag₁₂@(nBuPO₃)₉@Ag₃₆S₂₃, S@Ag₁₁@(nBuPO₃)₇(MoO₄)₂ @Ag₄₀S₂₇ and MoO₄@Ag₁₂@(nBuPO₃)₈S₆ @Ag₃₆S₂₄, respectively.     

Silver-Ethynide Clusters with Oxovanadate Components

Variation of the reaction conditions with AgC??CR (R?=?Ph, ^t Bu), ^t BuPO₃H₂, (Et₄N)VO₃ and AgNO₃ as starting materials afforded three isostructural globular neutral silver(I)-ethynide clusters incorporating the [( ^t BuPO₃)₄V₄O₈]^4? unit as an integral shell component, namely {(NO₃)₂@Ag₁₆(C??CPh)₄[( ^t BuPO₃)₄V₄O₈]₂(DEF)₆(NO₃)₂}, {(NO₃)₂@Ag₁₆(C??C ^t Bu)₄[( ^t BuPO₃)₄V₄O₈]₂(DMF)₆(NO₃)₂}·DMF·2H₂O and {(NO₃)₂@Ag₁₆(C??C ^t Bu)₄[( ^t BuPO₃)₄V₄O₈]₂(DMF)₆(NO₃)₂}·{(NO₃)₂@Ag₁₆(C??C ^t Bu)₄[( ^t BuPO₃)₄V₄O₈]₂(DMF)₄(py)₂(NO₃)₂}·DMF·5H₂O, in which the central cavity of each Ag₁₆ cluster is occupied by two nitrate ions that function as a template. Furthermore, from the reaction of AgC??C ^t Bu with (NH₄)₄[V₂O₄(d,l-citrate)₂]·4H₂O, we isolated a new high-nuclearity silver(I)-ethynide cluster [(VO₄)₂@Ag₃₄(C??C ^t Bu)₂₂(NO₃)₆]·8H₂O that encapsulates a pair of templating orthovanadate ions.     

Nestlike Silver(I) Thiolate Clusters with Tunable Emission Color Templated by Heteroanions

Four silver thiolate clusters, [H₃O][(Ag₃S₃)(BF₄)@Ag₂₇(tBuS)₁₈(hfac)₆H₂O] ⋅ H₂O ( 1 ; hfac = hexafluoroacetylacetone), [(Ag₃S₃)(CF₃CO₂)@Ag₃₀(tBuS)₁₆(CF₃CO₂)₉(CH₃CN)₄] ⋅ CF₃CO₂ ⋅ 4 CH₃CN ( 2 ), [(Ag₃S₃)(MoO₄)@Ag₃₀(tBuS)₁₆(CF₃CO₂)₉(CH₃CN)₄] ⋅ 2 CH₃CN ( 3 ), and [(Ag₃S₃)(CrO₄)@Ag₃₀(tBuS)₁₆(CF₃CO₂)₉(CH₃CN)₄] ⋅ 4 CH₃CN ( 4 ), were isolated. They have similar nestlike structures assembled by an [Ag₃S₃]³⁻ template together with one of the BF₄⁻, CF₃CO₂⁻, MoO₄²⁻, or CrO₄²⁻ anions. Interestingly, the solid-state emissions of 2 – 4 are dependent on the templating anions and are tunable from green to orange and then to red by changing the template from CF₃CO₂⁻ to MoO₄²⁻ and to CrO₄²⁻, and this may be correlated to the charge transfer between these templates to metal atoms. This work helps to understand the templating role of heteroanions and the relationship between structure and properties.     

General Assembly of Twisted Trigonal‐Prismatic Nonanuclear Silver(I) Clusters

A general class of C₃‐symmetric Ag₉ clusters, [Ag₉S(tBuC₆H₄S)₆(dpph)₃(CF₃SO₃)] ( 1 ), [Ag₉(tBuC₆H₄S)₆(dpph)₃(CF₃SO₃)₂] ? CF₃SO₃ ( 2 ), [Ag₉(tBuC₆H₄S)₆(dpph)₃(NO₃)₂] ? NO₃ ( 3 ), and [Ag₉(tBuC₆H₄S)₇(dpph)₃(Mo₂O₇)_0.5]₂ ? 2 CF₃COO ( 4 ) (dpph=1,6‐bis(diphenylphosphino)hexane), with a twisted trigonal‐prism geometry was isolated by the reaction of polymeric {(HNEt₃)₂[Ag₁₀(tBuC₆H₄S)₁₂]}_n, 1,6‐bis(diphenylphosphino)hexane, and various silver salts under solvothermal conditions. The structures consist of discrete clusters constructed from a girdling Ag₉ twisted trigonal prism with the top and bottom trigonal faces capped by diverse anions (i.e., S^2? and CF₃SO₃^? for compound 1 , 2×CF₃SO₃^? for compound 2 , 2×NO₃^? for compound 3 , and tBuC₆H₄S^? and Mo₂O₇^2? for compound 4 ). This trigonal prism is bisected by another shrunken Ag₃ trigon at its waist position. Interestingly, two inversion‐related Ag₉ trigonal‐prismatic clusters are dimerized by the Mo₂O₇^2? ion in compound 4 . The twist is amplified by the bulkier thiolate, which also introduces high steric‐hindrance for the capping ligand, that is, the longer dpph ligand. Four more silver–sulfur clusters (namely, compounds 5 – 8 ) with their nuclearity ranging from 6–10 were solely characterized by single‐crystal X‐ray diffraction to verify the above‐described synergetic effect of mixed ligands in the construction of Ag₉ twisted trigonal prisms. Surprisingly, only cluster 1 emits yellow luminescence at λ=584 nm at room temperature, which may be attributed to a charge transfer from the S 3p orbital to the Ag 5s orbital, or mixed with metal‐centered (MC) d¹⁰→d⁹s¹ transitions. Upon cooling from 300 to 80 K, the emission intensity was enhanced along with a hypsochromic shift. The good linear relationship between the maximum emission intensity and the temperature for compound 1 in the range of 180–300 K indicates that this is a promising molecular luminescent thermometer. Furthermore, cyclic voltammetric studies indicated that the diffusion‐ and surface‐controlled redox processes were determined for compounds 1 and 3 as well as compound 4 , respectively.     

Construction of Mesoporous Frameworks with Vanadoborate Clusters

A new porous vanadoborate was synthesized by employing the scale chemistry theory with the vanadoborate cluster V₁₀B₂₈. The twofold interpenetrated lvt network was assembled with zinc‐containing elliptical vanadoborate clusters and Zn polyhedra. The single lvt framework contains a three‐dimensional 38×38×20 ring channel system with the pore size (24.7×12.7 Å) reaching the mesoscale, thus indicating the possibility of constructing 3D ordered mesopores with vanadoborate clusters. The porosity of the SUT‐7 structure was confirmed by CO₂ adsorption of the as‐synthesized materials.     

Macrocyclic‐ligand Induced Synthesis of Aryl Ethynides with Divergent Silver(I) Clusters

Two structurally characterized metal‐cluster‐centered supramolecular architectures named [Ag₈(1,2‐(C ≡ C)₂‐C₆H₄ )( Py[6] )(CF₃CO₂ )₆] · 2.5MeOH ( 1 ) and [Ag₁₂(1,2,4,5‐(C ≡ C)₄C₆H₂ )( Py[6] )₂(CF₃SO₃ )₈]·4MeOH ·3H₂O ( 2 ) are synthesized through the interaction with a bowl‐shaped macrocyclic ligand Py[6] . Particularly, two dissimilar silver(I) clusters are resulted in 2 within the structure under the influence of the macrocyclic ligand Py[6] . Such dissimilarity of the silver(I) cluster is also reflected on the structural and photophysical differences between 1 and 2 .     

An Effective Method to Construct Cluster‐based Frameworks with Multifarious Structures,Luminescence, and Sorption Properties

An effective method was developed for the synthesis of three cluster‐based frameworks with multifarious secondary building units (SBUs) and various structures, which were formulated as [Me₂NH₂]₂[Zn₁₀(BTC)₆(μ₃‐O)(μ₄‐O)(H₂O)₅] · 3DMA · 9H₂O ( FJI ‐ 3 ), [Me₂NH₂]₂[Zn₉(μ₃‐OH)₂(BTC)₆(H₂O)₃] · 5DMA · 6H₂O ( FJI ‐ 4 ) and [Me₂NH₂][Zn₃(μ₃‐OH)(BTC)₂DMF] · H₂O ( FJI ‐ 5 ) (H₃BTC = 1,3,5‐benzenetricarboxylic acid, DMA = N,N′‐dimethyl acetamide and DMF = N,N′‐dimethyl formamide), respectively. X‐ray structural analysis reveals that FJI ‐ 3 displays 3D highly porous metal‐organic framework with four kinds of microporous cages constructed by two paddle‐wheel Zn₂(CO₂)₄, trimeric Zn₃O(CO₂)₆, and tetrameric Zn₄O(CO₂)₆ SBUs. FJI ‐ 4 exhibits 3D microporous MOFs with a dodecahedral cavities built by paddle‐wheel Zn₂(CO₂)₄ and trimeric Zn₃O(CO₂)₆. FJI ‐ 5 shows 3D microporous MOFs with an 1D channel assembled by the Zn₃O(CO₂)₆ SBUs. In addition, the fluorescence and sorption properties in these cluster‐based frameworks were also investigated. Furthermore, the method employed in this work may provide an useful approach to the design and synthesis of novel cluster‐based frameworks.     

Alkyltin Keggin Clusters Templated by Sodium

Dodecameric (Sn₁₂) and hexameric topologies dominate monoalkyltin–oxo cluster chemistry. Their condensation, triggered by radiation exposure, recently produced unprecedented patterning performance in EUV lithography. A new cluster topology was crystallized from industrial n ‐BuSnOOH, and additional characterization techniques indicate other clusters are present. Single‐crystal X‐ray analysis reveals a β‐Keggin cluster, which is known but less common than other Keggin isomers in polyoxometalate and polyoxocation chemistry. The structure is formulated [NaO₄(BuSn)₁₂(OH)₃(O)₉(OCH₃)₁₂(Sn(H₂O)₂)] (β‐NaSn₁₃). SAXS, NMR, and ESI MS differentiate β‐NaSn₁₃, Sn₁₂, and other clusters present in crude “n ‐BuSnOOH” and highlight the role of Na as a template for alkyltin Keggin clusters. Unlike other alkyltin clusters that are cationic, β‐NaSn₁₃ is neutral. Consequently, it stands as a unique model system, absent of counterions, to study the transformation of clusters to films and nanopatterns.     

Tuning CO2 Uptake and Reversible Iodine Adsorption in Two Isoreticular MOFs through Ligand Functionalization

The synthesis and characterization of two isoreticular metal–organic frameworks (MOFs), {[Cd(bdc)(4‐bpmh)]}_n?2 n(H₂O) ( 1 ) and {[Cd(2‐NH₂bdc)(4‐bpmh)]}_n?2 n(H₂O) ( 2 ) [bdc=benzene dicarboxylic acid; 2‐NH₂bdc=2‐amino benzene dicarboxylic acid; 4‐bpmh=N,N‐bis‐pyridin‐4‐ylmethylene‐hydrazine], are reported. Both compounds possess similar two‐fold interpenetrated 3D frameworks bridged by dicarboxylates and a 4‐bpmh linker. The 2D Cd‐dicarboxylate layers are extended along the a‐axis to form distorted square grids which are further pillared by 4‐bpmh linkers to result in a 3D pillared‐bilayer interpenetrated framework. Gas adsorption studies demonstrate that the amino‐functionalized MOF 2 shows high selectivity for CO₂ (8.4 wt % 273 K and 7.0 wt % 298 K) over CH₄, and the uptake amounts are almost double that of non‐functional MOF 1 . Iodine (I₂) adsorption studies reveal that amino‐functionalized MOF 2 exhibits a faster I₂ adsorption rate and controlled delivery of I₂ over the non‐functionalized homolog 1 .     

Extra Silver Atom Triggers Room‐Temperature Photoluminescence in Atomically Precise Radarlike Silver Clusters

Luminescent metal clusters show promise for applications in imaging and sensing. However, promoting emission from metal clusters at room temperature is a challenging task owing to the lack of an efficient approach to suppress the nonradiative decay process in metal cores. We report herein that the addition of a silver atom into a metal interstice of the radarlike thiolated silver cluster [Ag₂₇(S^tBu)₁₄(S)₂(CF₃COO)₉(DMAc)₄]?DMAc ( NC1 , DMAc=dimethylacetamide), which is non‐emissive under ambient conditions, produced another silver cluster [Ag₂₈(AdmS)₁₄(S)₂(CF₃COO)₁₀(H₂O)₄] ( NC2 ) that displayed bright green room‐temperature photoluminescence aided by the new ligand 1‐adamantanethiol (AdmSH). The 28th Ag atom, which hardly affects the geometrical and electronic structures of the Ag–S skeleton, triggered the emission of green light as a result of the rigidity of the cluster structure.     

Adamantyl‐ and Furanyl‐Protected Nanoscale Silver Sulfide Clusters

The silver salts of 1‐adamantanethiol (AdSH) and furan‐2‐ylmethanethiol (FurCH₂SH) were successfully applied as building blocks for ligand‐protected Ag₂S nanoclusters. The reaction of the silver thiolates [AgSAd]_x and [AgSCH₂Fur]_x with S(SiMe₃)₂ and 1,5‐bis(diphenylphosphino)pentane (dpppt) afforded three different clusters with 58, 94 and, 190 silver atoms. The intensely colored compounds [Ag₅₈S₁₃(SAd)₃₂] ( 1 ), [Ag₉₄S₃₄(SAd)₂₆(dpppt)₆] ( 2 ), and [Ag₁₉₀S₅₈(SCH₂Fur)₇₄(dpppt)₈] ( 3 ) were structurally characterized by single‐crystal X‐ray diffraction and exhibit different cluster core geometries and ligand shells. The diameters of the well‐defined sphere‐shaped nanoclusters range from 2.2 nm to 3.5 nm.     

A Luminescent Three-Dimensional Coordination Polymer Based on Cu(I) Halide Clusters Showing Dia Topology with 8-Fold Interpenetration

One interesting copper(I) halide-based coordination polymer with a formula of [Cu₄(Br)₄(bib)₂]_n (1) (bib = 1,4-bis(imidazol-2-methyl)butane) has been prepared by solvothermal method, and characterized by X-ray single crystal diffraction, elemental analyses, IR and TGA. Structure analyses reveal that the compound is constructed of copper(I) halide clusters and flexible bib ligands, which features a 8-fold interpenetrated 3D framework with 4-connected extended dia topology. Furthermore, the compound exhibits high thermal stability and intense fluorescent emission, and can be explored for potential red luminescent materials.     

Three novel topologically different metal–organic frameworks built from 3‐nitro‐4‐(pyridin‐4‐yl)benzoic acid

The design and synthesis of metal–organic frameworks (MOFs) have attracted much interest due to the intriguing diversity of their architectures and topologies. However, building MOFs with different topological structures from the same ligand is still a challenge. Using 3‐nitro‐4‐(pyridin‐4‐yl)benzoic acid (HL) as a new ligand, three novel MOFs, namely poly[[(N,N‐dimethylformamide‐κO)bis[μ₂‐3‐nitro‐4‐(pyridin‐4‐yl)benzoato‐κ³O,O′:N]cadmium(II)] N,N‐dimethylformamide monosolvate methanol monosolvate], {[Cd(C₁₂H₇N₂O₄)₂(C₃H₇NO)]·C₃H₇NO·CH₃OH}_n, ( 1 ), poly[[(μ₂‐acetato‐κ²O:O′)[μ₃‐3‐nitro‐4‐(pyridin‐4‐yl)benzoato‐κ³O:O′:N]bis[μ₃‐3‐nitro‐4‐(pyridin‐4‐yl)benzoato‐κ⁴O,O′:O′:N]dicadmium(II)] N,N‐dimethylacetamide disolvate monohydrate], {[Cd₂(C₁₂H₇N₂O₄)₃(CH₃CO₂)]·2C₄H₉NO·H₂O}_n, ( 2 ), and catena‐poly[[[diaquanickel(II)]‐bis[μ₂‐3‐nitro‐4‐(pyridin‐4‐yl)benzoato‐κ²O:N]] N,N‐dimethylacetamide disolvate], {[Ni(C₁₂H₇N₂O₄)₂(H₂O)₂]·2C₄H₉NO}_n, ( 3 ), have been prepared. Single‐crystal structure analysis shows that the Cd^II atom in MOF ( 1 ) has a distorted pentagonal bipyramidal [CdN₂O₅] coordination geometry. The [CdN₂O₅] units as 4‐connected nodes are interconnected by L^? ligands to form a fourfold interpenetrating three‐dimensional (3D) framework with a dia topology. In MOF ( 2 ), there are two crystallographically different Cd^II ions showing a distorted pentagonal bipyramidal [CdNO₆] and a distorted octahedral [CdN₂O₄] coordination geometry, respectively. Two Cd^II ions are connected by three carboxylate groups to form a binuclear [Cd₂(COO)₃] cluster. Each binuclear cluster as a 6‐connected node is further linked by acetate groups and L^? ligands to produce a non‐interpenetrating 3D framework with a pcu topology. MOF ( 3 ) contains two crystallographically distinct Ni^II ions on special positions. Each Ni^II ion adopts an elongated octahedral [NiN₂O₄] geometry. Each Ni^II ion as a 4‐connected node is linked by L^? ligands to generate a two‐dimensional network with an sql topology, which is further stabilized by two types of intermolecular OW—HW…O hydrogen bonds to form a 3D supramolecular framework. MOFs ( 1 )–( 3 ) were also characterized by powder X‐ray diffraction, IR spectroscopy and thermogravimetic analysis. Furthermore, the solid‐state photoluminescence of HL and MOFs ( 1 ) and ( 2 ) have been investigated. The photoluminescence of MOFs ( 1 ) and ( 2 ) are enhanced and red‐shifted with respect to free HL. The gas adsorption investigation of MOF ( 2 ) indicates a good separation selectivity (71) of CO₂/N₂ at 273 K (i.e. the amount of CO₂ adsorption is 71 times higher than N₂ at the same pressure).     

Rhombicuboctahedral Ag100: Four‐Layered Octahedral Silver Nanocluster Adopting the Russian Nesting Doll Model

Precise atomic structure of metal nanoclusters (NCs) is fundamental for elucidating the structure–property relationships and the inherent size‐evolution principles. Reported here is the largest known FCC‐based (FCC=face centered cubic) silver nanocluster, [Ag₁₀₀(SC₆H₃^3,4F₂)₄₈(PPh₃)₈]^?: the first all‐octahedral symmetric nesting Ag nanocluster with a four‐layered Ag₆@Ag₃₈@Ag₄₈S₂₄@Ag₈S₂₄P₈ structure, consistent symmetry elements, and a unique rhombicuboctahedral morphology distinct from theoretical predictions and previously reported FCC‐based Ag clusters. DFT studies revealed extensive interlayer interactions and degenerate frontier orbitals. The FCC‐based Russian nesting doll model constitutes a new platform for the study of the size‐evolution principles of Ag NCs.     

Luminescence Regulation of Silver‐Thiolate Clusters Protected by 1,2‐Dithiolate‐o‐carborane

Engineering the surface of the metal clusters with the core structure maintained and tuning their luminescence in a wide range is still a challenge in the nanomaterial research. We modified six mono‐pyridyl ligands with different electronic effects (conjugation effect or induction effect) on a superatomic silver cluster [Ag₁₄(C₂B₁₀H₁₀S₂)₆(CH₃CN)₈] (denoted as Ag₁₄) through in situ site‐specific surface engineering, and obtained the corresponding clusters [Ag₁₄(C₂B₁₀H₁₀S₂)₆(CH₃CN)₆(L₁/L₂)₂] (denoted as NC‐1, 2, L₁/L₂ = 4‐acetylpyridine/ 4‐carboxypyridine) and [Ag₁₄(C₂B₁₀H₁₀S₂)₆(L₃/L₄/L₅/L₆)₈] (denoted as NC‐3, 4, 5, 6, L₃/L₄/L₅/L₆ = 4‐phenylpyridine/4‐(1‐naphthyl)pyridine/9‐(4‐pyridine)anthracene/9‐(4‐pyridine)pyrene). Through the modification of the Ag₁₄ cluster, a wide‐range luminescence from blue to red was realized. This work might provide a practical guide for improving the emission performance of metal clusters via surface engineering.     

Molecular Pivot‐Hinge Installation to Evolve Topology in Rare‐Earth Metal–Organic Frameworks

Linker desymmetrization has been witnessed as a powerful design strategy for the discovery of highly connected metal–organic frameworks (MOFs) with unprecedented topologies. Herein, we introduce molecular pivot‐hinge installation as a linker desymmetrization strategy to evolve the topology of highly connected rare‐earth (RE) MOFs, where a pivot group is placed in the center of a linker similar to a hinge. By tuning the composition of pivot groups and steric hindrances of the substituents on various linker rotamers, MOFs with various topologies can be obtained. The combination of L‐SO₂ with C_2v symmetry and 12‐connected RE₉ clusters leads to the formation of a fascinating (4,12)‐c dfs new topology. Interestingly, when replacing L‐SO₂ with a tetrahedra linker L‐O, the stacking behaviors of RE‐organic layers switch from an eclipsed mode to a staggered stacking mode, leading to the discovery of an intriguing hjz topology. Additionally, the combination of the RE cluster and a linker [(L‐(CH₃)₆)] with more bulky groups gives rise to a flu topology with a new 8‐c inorganic cluster. The diversity of these RE‐MOFs was further enhanced through post‐synthetic installation of linkers with various functional groups. Functionalization of each linker with acidic and basic units in the mesoporous RE‐based PCN‐905‐SO₂ allows for efficient cascade catalytic transformation within the functionalized channels.     

2,11-二硫代[3.3]二聚对二甲苯与线性氟代二羧酸银之配位聚合物的合成

本文主要描述了由配体2,11-二硫代[3.3]二聚对二甲苯与线性氟代二羧酸银反应制得的三个银配合物的结构。这些配合物的结构因氟代二羧酸银的不同,差别也很大。配体2,11-二硫代[3.3]二聚对二甲苯与氟代丁二酸银反应得到的配合物1是一维链状结构;将银盐换成氟代戊二酸银则获得了三维立体结构的配合物2;若使用氟代己二酸银,则得到了二维多孔的配合物3。在多孔配合物3中,每个孔中容纳了两个客体三甲苯分子,在150℃时这些客体分子可被完全脱除。     

Formation of an Alkynyl‐Protected Ag112 Silver Nanocluster as Promoted by Chloride Released In Situ from CH2Cl2

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.     

Theoretical studies on anionic clusters of sulfate anions and carbon dioxide, SO 4?1/?2 (CO2)n, n?=?1?4

Geometry optimizations were performed on monoanionic and dianionic clusters of sulfate anions with carbon dioxide, SO₄^−1/−2(CO₂) _n , for n = 1–4, using the B3PW91 density functional method with the 6-311 + G(3df) basis set. Limited calculations were carried out with the CCSD(T) and MP2 methods. Binding energies, as well as adiabatic and vertical electron detachment energies, were calculated. No covalent bonding is seen for monoanionic clusters, with O₃SO–CO₂ bond distances between 2.8 and 3.0 ?. Dianionic clusters show covalent bonding of type [O₃S–O–CO₂]⁻², [O₃S–O–C(O)O–CO₂]⁻², and [O₂C–O–S(O₂)–O–CO₂]⁻², where one or two oxygens of SO₄⁻² are shared with CO₂. Starting with n = 2, the dianionic clusters become adiabatically more stable than the corresponding monoanionic ones. Comparison with SO₄^−1/−2(SO₂) _n and CO₃^−1/−2(SO₂) _n clusters, the binding energies are smaller for the present SO₄^−1/−2(CO₂) _n systems, while stabilization of the dianion occurs at n = 2 for both SO₄⁻²(CO₂) _n and SO₄⁻²(SO₂) _n , but only at n = 3 for CO₃⁻²(SO₂) _n .