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0 Introduction Recently, a considerable effort on crystal engi- neering has been devoted to the research of supramolecular assemblies because they show abun- dant topologic structures and offer possibilities for po- tential applications of functional mate… 相似文献
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Structural correlation in a series of eight silver(I) complexes bearing substituted phenylethynide ligands was systematically investigated through variation of the position or steric bulk of substituents on the aromatic ring. All coordination frameworks are constructed with the supramolecular synthon Ar--C triple bond C superset Ag(n) (Ar=4-MeC6H4, 3-MeC6H4, 2-MeC6H4, 4-tBuC6H4, 3,5-(CF3)2C6H3; n=4, 5), and the presence of coexisting ligands was found to influence the supramolecular assembly. The role of pi-pi stacking, C--Hpi and Ag-C(aromatic) interactions in stabilizing the coordination networks is also discussed. 相似文献
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ZHENG Shao-Liang YANG Jin-Hua CHEN Xiao-Ming 《结构化学》2009,28(11):1503-1508
A new neutral [Ag2(Hida)(NH3)2] molecule (1, H3ida = 1H-imidazole-4,5-dicarboxylic acid) has been synthesized and structurally characterized by single-crystal diffraction. Compound 1 crystallizes in monoclinic, space group C2/c with a = 18.3928(8), b = 8.3299(5), c = 13.682(7) A, β = 113.179(2)°, V = 1926.9(10)A^3, Z = 8 and Dc = 2.784 g·cm^-3. In the solid state, this disilver(I) compound can aggregate to furnish the energetically stable ligand-unsupported Ag^I-Ag^I interaction concomitant with significant photoluminescence changes in different aggregate states, and such argentophilicity interaction is also supported by molecular orbital calculations. 相似文献
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Novel mu(5)-eta(1),eta(1),eta(1),eta(1),eta(2) and mu(5)-eta(1),eta(1),eta(1),eta(2),eta(2) coordination modes of alkyl and aryl ethynide moieties are found in silver(I) complexes 1-5, and the metal-ligand distances can be classified into sigma, pi and mixed (sigma,pi) types. With the consistent square-pyramidal capping Ag(5) baskets of the ethynide moiety as supramolecular synthons, a series of two- and three-dimensional coordination networks are obtained. 相似文献
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Zhang JP Wang YB Huang XC Lin YY Chen XM 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,11(2):552-561
To verify whether attractive metallophilic interactions exist in the dimer-of-dimers [Cu(2)(ophen)(2)](2) (Hophen=1H-[1,10]phenanthrolin-2-one) (1), we designed and synthesized a series of such [M(2)L(2)](2) structures by varying the d(10) metal and/or the ligand (M=Cu(I) or Ag(I), L=ophen or obpy; Hobpy=1H-[2,2']bipyridinyl-6-one), and have successfully obtained three dimers-of-dimers: [Ag(2)(ophen)(2)](2).6 H(2)O (2), [Cu(2)(obpy)(2)](2) (3), and [Ag(2)(obpy)(2)](2).4.5 H(2)O.0.5 DMF (4). X-ray analyses of these structures show that interdimer M-M separations in [Ag(2)-(ophen)(2)](2) (3.199 A) are remarkably shorter than those in [Cu(2)(ophen)(2)](2) (3.595 A). Shorter interdimer M-M separations are found in the structures of [M(2)(obpy)(2)](2) (2.986 and 2.993 A in [Cu(2)(obpy)(2)](2), 3.037 to 3.093 A in [Ag(2)(obpy)(2)](2)), in which the pi systems are smaller than in the complexes with the ophen ligand. Detailed structural comparison of these dimers-of-dimers indicates that the interdimer, face-to-face pi-pi interactions repulse rather than support the interdimer metal-metal attractive interactions. This study also yields qualitative comparison of the strengths between argentophilic, cuprophilic, and face-to-face pi-pi interactions. DFT calculations on the four dimers-of-dimers further support the above deduction. The structure of a trimer-of-dimers [Ag(2)(obpy)(2)](3) (Ag-Ag 3.171 to 3.274 A) is further evidence that the oligomerization of the [M(2)L(2)] molecules is favored by stronger metallophilic and weaker face-to-face pi-pi interactions. 相似文献
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The Potential of the Diarsene Complex [(C5H5)2Mo2(CO)4(μ,η2-As2)] as a Connector Between Silver Ions
Dr. Mehdi Elsayed Moussa Jana Schiller Dr. Eugenia Peresypkina Dr. Michael Seidl Dr. Gábor Balázs Pavel Shelyganov Prof. Dr. Manfred Scheer 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(63):14315-14319
The reaction of the organometallic diarsene complex [Cp2Mo2(CO)4(μ,η2-As2)] ( B ) (Cp = C5H5) with Ag[FAl{OC6F10(C6F5)}3] (Ag[FAl]) and Ag[Al{OC(CF3)3}4] (Ag[TEF]), respectively, yields three unprecedented supramolecular assemblies [(η2- B )4Ag2][FAl]2 ( 4 ), [(μ,η1:η2- B )3(η2- B )2Ag3][TEF]3 ( 5 ) and [(μ,η1:η2- B )4Ag3][TEF]3 ( 6 ). These products are only composed of the complexes B and AgI. Moreover, compounds 5 and 6 are the only supramolecular assemblies featuring B as a linking unit, and the first examples of [AgI]3 units stabilized by organometallic bichelating ligands. According to DFT calculations, complex B coordinates to metal centers through both the As lone pair and the As−As σ-bond thus showing this unique feature of this diarsene ligand. 相似文献
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Dr. Alba Vellé Dr. Luis Rodríguez-Santiago Prof. Mariona Sodupe Dr. Pablo J. Sanz Miguel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(5):997-1002
Metallophilicity is an essential concept that builds upon the attraction between closed shell metal ions. We report on the [M2(bisNHC)2]2+ (M=AuI, AgI; NHC=N-heterocyclic carbene) systems, which display almost identical features in the solid state. However, in solution the Au2 cation exhibits a significantly higher degree of rigidity owed to the stronger character of the aurophilic interactions. Both Au2 and Ag2 cationic constructs are able to accommodate Ag+ ions via M–M interactions, despite their inherent Coulombic repulsion. When electrostatic repulsion between host and guest is partially diminished, M–M distances are substantially shortened. Quantum chemical calculations estimate intermetallic bond orders up to 0.2. Although at the limit of (or beyond) the van der Waals radii, metallophilic interactions are responsible for their behavior in solution. 相似文献
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Zheng SL Volkov A Nygren CL Coppens P 《Chemistry (Weinheim an der Bergstrasse, Germany)》2007,13(30):8583-8590
An isolated silver(I) ammonia monomer, a dimer, and a novel dimer containing an intercalated water molecule have been embedded as guests in supramolecular frameworks, [Ag(NH3)2][(H2thpe)(H3thpe)].MeCN (1), [{Ag(NH3)2}2][(H2thpe)2]4.25 H2O (2), and [{Ag(NH3)2}-H2O-{Ag(NH3)2}][(H2thpe)(2)]benzene (3) (H3THPE=tris(hydroxyphenyl)ethane). The [{Ag(NH3)2}2]2+ dimer is not stable as an isolated entity, but is stabilized by hydrogen bonding in the supramolecular framework. The water-intercalated silver(I) ammonia dimer, which constitutes a novel species, is also subject by hydrogen bonding in concentrated solutions. The destabilization energy of the dimer relative to isolated monomers is calculated to be approximately 300 kJ mol(-1) by both perturbation methods and DFT theory. For the water-intercalated dimer it is calculated to be approximately 200 kJ mol(-1) according to the BSSE-corrected MP2 calculation. The different aggregate states show a dramatic variation of absorption and emission properties, in accordance with the concentration dependent red-shift observed in solutions. Natural-bond-orbital analysis shows that the disilver-ammonium-aquo "sandwich" cation in 3 is stabilized by interaction between the pi lone pair orbital on the oxygen atom of the water molecule and Ag(I)--N sigma antibonding molecular orbital. 相似文献
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A series of 13 silver(I) double and multiple salts containing 1,3‐butadiynediide, C42?, were synthesized by dissolving the silver carbide Ag2C4 in a concentrated aqueous solution of one or more of the silver salts AgNO3, AgCF3CO2, AgC2F5CO2, AgF, AgBF4, and AgPF6. The 1,3‐butadiynediide anion invariably adopts a μ4,μ4 coordination mode in these compounds, which indicates that the Ag4?C?C? C?C?Ag4 moiety can be used as a new type of metalloligand supramolecular synthon for the construction of coordination networks. Fine‐tuning with various ancillary anionic ligands caused the Ag4 aggregate at each ethynide terminus to adopt a butterfly‐shaped, planar, or barblike configuration, within which the silver–ethynide interactions can be classified into three types: σ, π, and mixed (σ,π). The effect of coexisting nitrile ligands and quaternary ammonium salts on supramolecular assembly with the above synthon was also explored. The hydrolysis of PF6? and BF4? led to the formation of the quadruple salt Ag2C4?4 AgNO3?AgPF2O2?Ag3PO4 and a novel (F)2(H2O)18 hydrogen‐bonded tape in the triple salt Ag2C4?2 AgF? 10 AgC2F5CO2?CH3CN?12 H2O, respectively. The largest silver–ethynide cluster aggregate described to date, (C4)3@Ag18, occurs in 3 Ag2C4? 12 AgC2F5CO2?5[(BnMe3N)C2F5CO2]? 4 H2O (Bn=benzyl). 相似文献
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