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1.
The one-dimensional coordination polymer 1[SbCl3(pyz)] ( 1 ) and the three-dimensional frameworks 3[Sb2Cl6(pyz)3] ( 2 ) and 3[Sb2I6(pyz)3] ( 3 ) were obtained from SbX3 (X: Cl, I) and pyrazine (pyz). These coordination polymers are, to the best of our knowledge, among the first Sb-based coordination polymers constructed from antimony halides and N-donor ligands. While the Sb3+-cations in 1 are coordinated in a square-pyramidal coordination sphere indicating a stereochemically active lone-pair, no stereochemically active Sb-lone-pair is present in 2 and 3 having octahedral coordination spheres around SbIII. Since 2 can be obtained by heating of 1 , the character of the Sb-lone-pair in 1 can be changed by thermal treatment. Thereby the interlinkage is increased via an additional pyrazine molecule resulting in the octahedral coordination in 2 .  相似文献   

2.
Four new d10 heterometallic coordination polymers have been obtained using three Schiff-base ligands, zinc(II) nitrate, and dicyanometallates: 1[{Zn3(Salen)2}{μ-Au(CN)2}2] (1); 1[Zn(Saldmen){μ-Ag(CN)2}]·2H2O (2); 1[Zn(Salampy){μ-Ag(CN)2}] (3); 1[Zn(Salampy){μ-Au(CN)2}] (4). The Schiff bases are obtained from condensation of salicylaldehyde with ethylenediamine (H2Salen); N,N-dimethyl-ethylenediamine (HSaldmen) and, respectively, 2-aminomethyl-pyridine (HSalampy). The dicyanometallates are K[Ag(CN)2] and K[Au(CN)2]. The compounds were characterized by X-ray single-crystal diffraction, infrared spectroscopy, UV–vis spectroscopy, and elemental analysis. In compound 1, the homotrimetallic units, {Zn3(salen)2}2+, are connected by two [Au(CN)2]? bridges, forming a 1-D double chain. In compounds 24, the crystal structures show polymeric zigzag chains generated by the mononuclear zinc(II) nodes and [M(CN)2]? spacers. The luminescence properties of the new heterometallic polymers have also been investigated.  相似文献   

3.
Six heterometallic Zn(II) coordination polymers, Zn(H2O)3(FNA) (1), [NH4]2[Zn(H2O)2(FNA)2] (2), [ZnNa2(FNA)2]·3H2O (3), [ZnK2(FNA)2]·H2O (4), [ZnRb2(FNA)2]·2H2O (5) and [ZnMg(FNA)2]·4H2O (6) (H2FNA = 4-nitrobenzene-1,2-dicarboxylic acid), were synthesised by introducing different alkali/alkaline earth (AeI/AeII) metals. These complexes exhibit diverse structures with the different AeI/AeII metals used and distinct ligand coordination modes the ions provide. For 1 and 2, the Zn(II) centres with distorted octahedra are connected by FNA to form 1-D chain structures. The Zn(II) centres in 36 with distorted tetrahedra are linked by FNA to form 2-D anionic grid layers. For 35, these 2-D anionic grid layers are connected by alkali metal (Na, K and Rb) with the O–AeI–O connectivity to exhibit 3-D framework structures, while 6 features a 2-D Zn–Mg network. Luminescence properties of 16 have been investigated.  相似文献   

4.
A novel organic-inorganic hybrid polyoxovanadate, [Ni(bpp)2]2(V4O12) (bpp= 1,3-bi-4-pyridylpropane), was hydrothermally synthesized from a mix.ture of NiCl2*6H2O, NH4VO3, bpp, EtOH and H2O. The crystal structure consists of ∞^2[Ni(bpp)2]^2+, two-dimensional networks interpenetrating perpendicularly with each other, and (V4O12)^4-, cyclic tetranuclear clusters linking the ∞^2[Ni(bpp)2]^2+ networks to form a three-dimensional coordination framework. The crystal belongs to tetragonal space group I41/a with unit cell parameters, a= 2.14705 nm, c= 1.29293 nm. UV-Vis-NIR reflectance spectroscopy study revealed insulator nature for the crystal with an optical energy gap of 2.70 eV.  相似文献   

5.
By employing one bridging ligand, 2,4‐pyridinedicarboxylate (2,4‐pda2?), three one‐dimensional (1D) coordination polymers of [Cu(2,4‐pda)(H2O)2] ( 1 ), {[Cu4(2,4‐pda)4(H2O)8]·3H2O} ( 2 ), and {[Cd(2,4‐pda)(H2O)3]·H2O} ( 3 ) were synthesized. A simple zigzag polymeric chain is observed for both 1 and 3 , but a railroad‐like zigzag polymeric chain is observed for 2. Almost all water molecules, whether coordinated or not, are involved in hydrogen bonding interactions and help to tie up the 1D polymeric chains of 1‐3 into a three‐dimensional (3D) network. A comparison about the coordination geometries in all similar coordination polymers available to date is also included.  相似文献   

6.
To understand the structural and thermal properties of the mixed crystals, thermogravimetric (TG) and differential thermal analysis (DTA), and FTIR and Raman spectral studies were carried out for the mixed crystals of Zna/Mgb ammonium sulfate of composition namely 'a' (fraction by mass of salt Zn[NH4]2[SO4]2·6H2O to the total salt (both Zn[NH4]2[SO4]2·6H2O, Mg[NH4]2[SO4]2·6H2O or it can be explained as ZnaMgb[NH4]2[SO4]2·6H2O, a + b =1), and a = 0.1, 0.25, 0.333, 0.5, 0.666, 0.75 and 0.9 grown by a solution technique. From the correlation and analysis of the results obtained for the various crystals, the desolvation, decomposition, crystalline transition phenomena were identified. By close comparison of the endotherms, obtained for the various crystals, it was found that isomorphous substitution takes place in the crystals. Up to 0.5, Zn2+ ion replaces isomorphous Mg2+ ions in the lattice sites of Mg[NH4]2[SO4]2·6H2O and above 0.5, Mg2+ ions occupies the Zn2+ ion in the lattice sites of Zn[NH4]2[SO4]2·6H2O. Both crystals belong to monoclinic system with P 2(1)/a symmetry. The vibrations of NH4 + ion, SO4 2- ion, the complex [Mg(OH2)6]2+ the complex [Zn(OH2)6]2+ and the three different water molecules are identified. The linear distortion of SO4 2- ion is found to be greater than its angular distortion, while the NH4 + ion has suffered more angular distortion. The possibility of free rotation of the NH4 + ion is ruled out.  相似文献   

7.
A new Keggin-type heteropolyanion decorated with dinuclear copper-organic coordination ions, {[Cu(Phen)(μ-Cl)Cu(Phen)2]2[SiW12O40]}· H2O (I), has been hydrothermally synthesized and structurally characterized by IR spectroscopy and single-crystal X-ray diffraction. X-ray crystallography analysis showed that two dinuclear copper-organic [Cu(Phen)(μ-Cl)Cu(Phen)2]3+ units are supported on the reduced α-Keggin polyoxoanion [SiW12O40]6? via two terminal oxygen atoms from opposite sides of the Keggin polyoxoanion, and I further acts as a neutral molecular unit for the construction of a one-dimensional chain-like framework by \(C - H \cdots Cl\) hydrogen bonds and π-π-stacking interactions.  相似文献   

8.
Three coordination polymers containing Cd(II) and Co(II), connected via 4-[(3-pyridyl)methylamino]benzoate (L?), have been synthesized in hydrothermal conditions. In [Cd(L)Cl] n (1), adjacent Cd(II) cations are linked by carboxylates to give a dinuclear cluster. Pairs of L? bridge the dinuclear cluster to form double helical chains, and these chains are further linked by Cl? to produce a 4-connected net with (42?·?63?·?8) topology. [CdL2] n (2) contains 1-D ladder-like chains. The packing structure displays a 3-D supramolecular structure, with π?···?π interactions stabilizing the framework. [CoL2] n (3) has a 2-D extended supramolecular structure via π?···?π interactions of 1-D coordination polymers of 3. The crystal structures of 1–3 have been determined by single-crystal X-ray diffraction. Luminescent properties for 1 and 2 are discussed.  相似文献   

9.
The dinuclear ZnII complex [Zn2L(DNBA)2]BPh4 · EtOH ( 1 ) (DNBA = 3,5‐dinitrobenzonic acid) with an asymmetric dinuclear ligand, N‐4‐methyl‐homopiperazine‐N′‐[N‐(2‐pyridylmethyl)‐N‐2‐(2‐pyridylethyl)amine]‐1,3‐diamino‐propan‐2‐ol (HL), was synthesized and characterized. Single crystal X‐ray crystallographic analysis shows that the coordination around the two ZnII ions in 1 is significantly asymmetric, and the distance between both atoms is 3.426 Å, which is close to the Zn···Zn distance in related natural dinuclear metalloenzymes. Phosphodiesterase activity of Zn2L in situ formed from a 2:1 mixture of Zn2+ ion and HL was investigated using bis(4‐nitrophenyl) phosphate (BNPP) as substrate. The pH dependence of the BNPP cleavage in aqueous buffer media reveals a bell‐shaped pH‐kobs profile with an optimum at about pH 7.9, which is parallel to the formation of the dinuclear species Zn2L‐OH obtained from the potentiometric titration. The catalytic rate constant (kcat) is 6.30 × 10–4 s–1 at pH 7.9 and 25 °C, which is approx. 108‐fold higher than that of the uncatalyzed reaction. The homopiperazine bound deprotonated Zn‐OH group is responsible for the hydrolysis reaction. The possible mechanism for the BNPP cleavage promoted by Zn2L is proposed on the basis of kinetic and spectral analysis.  相似文献   

10.
By employing one bridging ligand, 2,5‐pyridinedicarboxylate (2,5‐pda2?), in the presence or absence of another bridging ligand, 4,4′‐bipyridine (4,4′‐bpy), one one‐dimensional (1D) {[Co2(2,5‐pda)(2,5‐Hpda)2(4,4′‐bpy)(H2O)3]·6H2O} ( 1 ) and two two‐dimensional (2D) coordination polymers, {[Cu3(2,5‐pda)3(H2O)3]·6H2O} ( 2 ) and {[Co(2,5‐pda)(H2O)]·2H2O} ( 3 ) were synthesized. Complexes 2 and 3 are characterized as concomitant polymorphs from a one‐pot reaction at ambient temperature. A comparison of the coordination geometries of all neutral and anionic coordination polymers containing {Mx(2,5‐pda)y(H2O)z} available to date is presented.  相似文献   

11.
The coordination compounds of group 12 halides with 2,2′-bipyridine (bpy) and 1,10-phenanthroline (phen), 2[CdF2(bpy)2]·7H2O (1), [ZnI(bpy)2]+·I3? (2), [CdI2(bpy)2] (3), [Cd(SiF6)H2O(phen)2]·[Cd(H2O)2(phen)2]2+·F·0.5(SiF6)2–·9H2O (4), [Hg(phen)3]2+·(SiF6)2–·5H2O (5), [ZnBr2(phen)2] (6), 6[Zn(phen)3]2+·12Br·26H2O (7) and [ZnI(phen)2]+·I (8), have been synthesized and characterized by X-ray crystallography, IR spectroscopy, elemental and thermal analysis. Structural investigations revealed that metal?:?ligand stoichiometry in the inner coordination sphere is 1?:?2 or 1?:?3. A diversity of intra- and intermolecular interactions exists in structures of 18, including the rare halogen?halogen and halogen?π interactions. The thermal and spectroscopic properties were correlated with the molecular structures of 18. Structural review of all currently known coordination compounds of group 12 halides with bpy and phen is presented.  相似文献   

12.
Two multiple-layer heterometallic MnII–AgI coordination polymers, {MnII(ampyz)(H2O)[Ag2I(CN)3][AgI(CN)2]·ampyz} n (1) and {[MnII(benzim)2[AgI(CN)2]2][(benzim)AgI(CN)]·H2O} n (2) where ampyz = 2-aminopyrazine and benzim = benzimidazole, have been prepared and structurally characterized. Compound 1 reveals a multiple-layer two-dimensional network with strong hexanuclear argentophilic interactions leading to an infinite three-dimensional framework. Compound 2 has an unprecedented double-layer two-dimensional squared grid-type network with (4,4) topology through AgI···AgI and π–π interactions between two adjacent squared layers. These double-layer networks of 2 are linked to others by π–π interactions, leading to a three-dimensional framework.  相似文献   

13.
Two couples of new compounds templated by the polyanion [SiW12O40]4?,[Hbix][CuI(bix)]3[SiW12O40]·4H2O (1) and [CuII(H2O)(Hbix)2(bix)]2[CuII(H2O)2(Hbix)2(bix)][SiW12O40]3·4H2O (2) (bix = 1,4-Bis(imidazol-1-ylmethyl)benzene), [CuI(bbi)]4[SiW12O40]·2H2O (3) and [CuII(bbi2)]2[SiW12O40] (4) (bbi = 1,1′-(1,4-butanediyl)bis(imidazole)) were hydrothermally synthesized, and characterized by elemental analyses, IR spectroscopy, thermogravimetric analyses and single X-ray diffraction. Compounds 1 and 2 were synthesized from the same reactants but exhibited distinct structures which could be ascribed to the different ratios of the reactant bix to CuII. In compound 1, the higher ratio of bix results in the transformation of the CuII to CuI, the [SiW12O40]4? templates direct the CuI–bix coordination polymers to form a 3D supramolecular framework with grid-like channels along two directions. The [SiW12O40]4? templates in compound 2 locate in the voids of the 3D supramolecular network constructed by CuII–bix coordination polymers, which exhibits the interdigitation fashion in both the formation of the 2D layer and the 3D framework. Compounds 3 and 4 were synthesized similar to 1 and 2, except for the change of bix to bbi. In compound 3, the CuI–bbi polymers form a supramolecular metal–organic host framework with rhombic channels in which the SiW12 templates reside. Compound 4 shows a framework with hexagonal channels constructed by CuII–bbi coordination polymers which accommodated the SiW12 templates.  相似文献   

14.
In this study, we have deliberately utilized the second-sphere coordination approach into the construction of supramolecular inclusion solids Cl ? [H2 L1]·[InCl4] (Crystal I) and Br ? [H2 L1]·[TeBr6] (Crystal II). The chloride or bromine anions can be encapsulated inside the host assemblies formed by the diamine molecule (4,6-dimethyl-1,3-phenylene) bis(N,N-dibenzylmethane) (L1) and the metal complexes ([InCl4]? and [TeBr6]2?) via second-sphere interactions. The inclusion complexes have been structurally characterized by X-ray crystallography, indicating that weak C–H···Cl and C–H···Br hydrogen bonding synthons play a significant role in the construction of host framework. 2-D networks are formed in both complexes by the interconnection of 1-D networks through the multiple weak hydrogen bonding interactions with [InCl4]? or [TeBr6]2?. The guest Cl? or Br? anions are encapsulated inside the host cages through N–H···Cl hydrogen bonds. The inclusion selectively was studied for the two host assemblies.  相似文献   

15.
Novel double complex salts, [Zn(DMF)6]2[SiW12O40] · 2H2O (I) and [Zn(H2O)2(DMF)4][Zn(DMF)6]2[PW12O40]2 · 6DMF (II) (DMF = N,N-dimethylformamide), were prepared by the reaction of Zn2+ and heteropoly acids Hx[EW12O40] · xH2O (E = P, X = 3, E = Si, X = 4) in DMF. Compounds I and II were studied by X-ray diffraction (СIF files CCDC nos. 1497570 (I) and 1497571 (II)) and IR spectroscopy.  相似文献   

16.
《Solid State Sciences》2012,14(8):1117-1125
Aiming at exploring the effect of substituting groups of three structurally related ligands, 5,6-diethyl-pyrazine-2,3-dicarboxylic acid (H2L1), 5,6-diphenyl-pyrazine-2,3-dicarboxylic acid (H2L2), and dibenzo[f,h]quinoxaline-2,3-dicarboxylic acid (H2L3), seven new coordination polymers constructed from these three substituted dicarboxylate ligands, {[Zn(L1)(H2O)3]·2H2O} (1), {[Cd2(L)4(H2O)]·3H2O} (2), [Zn(L2)(CH3OH)] (3), {[Zn(L2)(H2O)2]·H2O} (4), {[Zn(L)]·H2O} (5), [Zn2(L3)(DMF)4] (6), [Zn(L3)(2,2ʹ-bipy)(H2O)] (7), have been prepared and structurally characterized. 1 is a 1D chain structure in which ZnII ion is six-coordinated with octahedron geometry. 2 is also a 1D chain structure in which there are two crystallographically independent CdII ions in the asymmetric unit and exist transformative L ligands in the resulting complex. 3 and 4 both possess 2D layer network with the same (4, 82) topology, while the two complexes take different coordination modes during the forming of the compounds. 5 has a 1D chain structure based on the transformative L ligand in which ZnII ion is five-coordinated with bipyramidal geometry. 6 and 7 both have 1D chain structure constructed from L3 ligand. Thereinto, ZnII ion in 6 is five-coordinated by three oxygen atoms from two individual L3 ligands and two oxygen atoms from two DMF molecules. While in 7 there are also five coordination sites occupied by two carboxylate oxygen atoms from two L3 ligands. In addition, the compounds are characterized by elemental analysis, IR spectra. The luminescent properties of the compounds are also discussed and exhibit strong fluorescent emissions in the solid state.  相似文献   

17.
Reactions of copper(I) halides (Cl, Br, I) with 1‐methyl‐1, 3‐imidazoline‐2‐thione (mimzSH) in 1 : 2 molar ratio yielded sulfur‐bridged dinuclear [Cu2X2(μ‐S‐mimzSH)21‐S‐mimzSH)2] (X = I, 1 , Br, 2 ; Cl, 3 ) complexes. Copper(I) iodide with 1,3‐imidazoline‐2‐thione (imzSH2) and Ph3P in 1 : 1 : 1 molar ratio has also formed a sulfur‐bridged dinuclear [Cu2I2(μ‐S‐imzSH2)2(PPh3)2] ( 4 ) complex. The central Cu(μ‐S)2Cu cores form parallelograms with unequal Cu–S bond distances {2.324(2), 2.454(3) Å} ( 1 ); {2.3118(6), 2.5098(6) Å} ( 2 ); {2.3075(4), 2.5218(4) Å} ( 3 ); {2.3711(8), 2.4473(8) Å} ( 4 ). The Cu···Cu separations, 2.759–2.877Å in complexes 1 – 3 are much shorter than 3.3446Å in complex 4 . The weak intermolecular interactions {H2CH···S# ( 2 ); CH···Cl# ( 3 ); NH···I# ( 4 )} between dimeric units in complexes 2 – 4 lead to the formation of linear 1D polymers.  相似文献   

18.
Trigonal Crystallizing Metal(II) Hexacyanoferrates(II) M2II[Fe(CN)6] According to X-ray powder diagrams, Ca2[Fe(CN)6], Cd2[Fe(CN)6], Zn2[Fe(CN)6] · 2 H2O, Pb2[Fe(CN)6] and the firstly described compounds Zn2[Fe(CN)6] · 2 NH3 and Sn2[Fe(CN)6] crystallize trigonal containing one formula unit in the unit cell. Ca2[Fe(CN)6] and Cd2[Fe(CN)6] are belonging to the space group D—P3 1m, the other compounds to D—P3 m1. The latters are described as coordination polymers with a coordination number 4 for Zn and 3 for Sn and Pb, respectively.  相似文献   

19.
Three coordination compounds [Mn3(dmb)6(H2O)4(4, 4′‐bpy)3(EtOH)]n ( 1 ) and [M(dmb)2(pyz)2 (H2O)2] [MII = Co ( 2 ), Mn ( 3 )] (Hdmb = 2, 6‐dimethoxybenzoic acid, 4, 4′‐bpy = 4, 4′‐bipyridine, pyz = pyrazine) were synthesized and characterized by single‐crystal X‐ray diffraction analysis. Compound 1 consists of infinite 1D polymeric chains, in which the metal entities are bridged by 4, 4′‐bpy ligands. There are four crystallographically independent MnII atoms in the linear chain with different coordination modes, which is only scarcely reported for linear polymers. The isostructural crystals of 2 and 3 are composed of neutral mononuclear complexes. In crystal the complexes are combined into chains by intermolecular O–H ··· N hydrogen bonds and π–π interactions between antiparallel pyrazine molecules.  相似文献   

20.
Using 4-methylbenzenethiolates of Zn or Cd as precursors and 4,4′-bipyridine (4,4′-bpy) as bridges, we have synthesized three new Zn(II)/Cd(II) coordination polymers, {[Cd(4,4′-bpy)2(NCS)2] · 2(SC6H4CH3-4)2} n (1), {[Zn(4,4′-bpy)(SC6H4CH3-4)2] · DMF} n (2) and {[Zn(4,4′-bpy)(SC6H4CH3-4)2] · H2O · 0.5CH3OH} n (3). Compound 1 is a 2-D sheet-like square polymer in which four 4,4′-bpy ligands and two isothiocyanate ligands complete the octahedral Cd(II) coordination sphere. Compounds 2 and 3 have similar coordination around Zn(II), but have different polymer structures. In 2, Zn(II) centers are linked via a bidentate 4,4′-bipyridine to form 1-D twisted arched chains, which is a new structural type for Zn(II). Compound 3 has 1-D zigzag chains. The 2-D sheets in 1 and 1-D chains in 2 and 3 are assembled via intermolecular C–H ··· π and C–H ··· S interactions into 3-D supramolecular networks. C–H ··· S interactions are a vital factor in constructing the sulfur-containing coordination polymers. Different coordination modes and packing schemes in 13 show that the guest molecule has a critical influence on formation of polymers.  相似文献   

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