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1.
A dinuclear copper(II) complex, [CuII2(L)2] is afforded by the reaction of CuCl2 · 2H2O with a triazenido ligand, 1-[(2-carboxymethyl) benzene]-3-[2-carboxybenzene] triazene (H2L). Structural investigation shows that the copper-copper distance [2.3985(7) Å] is significantly shorter than the sum of the van der Waals radii of Cu (1.40 Å), suggesting that there are metal-metal bonds in [CuII2(L)2]. In solid, there is a strong antiferromagnetic interaction between copper(II) ions (J = –135.6 cm–1). In homogeneous environment, [CuII2(L)2] shows electrocatalytic activities for hydrogen generation both from acetic acid with a turnover frequency (TOF) of 32 mol of hydrogen per mole of catalyst per hour [mol(H2) · mol–1(catalyst) · h–1] at an overpotential (OP) of 941.6 mV, and neutral buffer with a TOF of 512 mol(H2) · mol–1(catalyst) · h–1 at an OP of 836.7 mV.  相似文献   

2.
Two novel copper(II) coordination polymers, [CuNa2(Hnta)2]n ( 1 ) and {[CuNa2(pht)2(H2O)]·H2O}n ( 2 ) (H3nta = nitrilotriacetate acid, H2pht = o‐phthalic acid), have been synthesized and characterized.The sodium ions play an important role in the formation of the multi‐dimensional structures. The X‐ray structure of [CuNa2(Hnta)2]n ( 1 ) is three‐dimensionally cross‐linked with building blocks [Cu(Hnta)2]2—connected by three sodium ions. The structure of {[CuNa2(pht)2(H2O)]·H2O}n ( 2 ) can be described as pht units connected by Na ions via Na—O bonds to form chains, which are linked by CuII ions to make a 2D network. The IR spectra and thermal properties are also reported.  相似文献   

3.
The preparation, crystal structures, and thermal properties of [Ca(pyr)2(4‐nba)2]n ( 1 ) (pyr = pyrazole; 4‐nba = 4‐nitrobenzoate) {[Ca(H2O)2(3‐npth)] · H2O}n ( 2 ) (3‐npth = 3‐nitrophthalate), [Mg(H2O)5(3‐npth)] · 2H2O ( 3 ), and [Mg(H2O)4(2‐nba)2] ( 4 ) (2‐nba = 2‐nitrobenzoate) are reported. The anhydrous CaII compound 1 and the diaqua CaII‐3‐nitrophthalate monohydrate 2 are one‐dimensional coordination polymers containing a hexacoordinate CaII ion located on a center of inversion in 1 and a heptacoordinated CaII ion in 2 . In 1 , the 4‐nitrobenzoate moiety acts as a μ2‐bridging bidentate ligand, whereas the 3‐nitrophthalate anion exhibits a μ3‐bridging pentadentate coordination mode in 2 . The hexacoordinate MgII‐containing compounds 3 and 4 do not contain a [Mg(H2O)6]2+ unit and the central MgII ion is coordinated to at least one monodentate carboxylate unit namely the monodentate 3‐npth molecule in 3 and two trans monodentate 2‐nba molecules in 4 . Hydrogen bonding between the lattice water molecules results in the formation of a water dimer in 3 . A comparative study of 17 alkaline earth nitrocarboxylates is described.  相似文献   

4.
Two tetranuclear clusters of formula [M4L4(HOMe)4] {H2L = (E)‐1‐[(2‐(hydroxymethyl)phenylimino)methyl]naphthalen‐2‐ol} [M = Co ( 1 ), Ni ( 2 )] were hydrothermally synthesized by reaction of M(OAc)2 · 4H2O with H2L and NaOH in MeOH. X‐ray crystal structure analysis revealed that complexes 1 and 2 are isostructural. In the core of the structures, four MII ions and four oxygen atoms occupied alternate vertices of [M4O4] cubane. The magnetic property measurements of 1 and 2 revealed that overall ferromagnetic MII ··· MII exchange interactions exist in both complexes.  相似文献   

5.
Three 1H‐benzimidazole‐5‐carboxylate (Hbic)‐based coordination polymers, {[Ni(H2O)(Hbic)2] · 2H2O}n ( 1 ), {[Ni(H2O)2(Hbic)2] · 3H2O}n ( 2 ), and {[Co2(H2O)4(Hbic)4] · 4DMF · 3H2O}n ( 3 ) were obtained by reactions of the ligand H2bic and NiII or CoII salts in the presence of different structure directing molecules. They were structurally characterized by single‐crystal X‐ray diffraction, IR spectra, elemental analysis, thermal stability, luminescent, and magnetic measurements. Structural analysis suggests that the three polymers exhibit a 2D (4, 4) layer for 1 and 1D linear double chains for both 2 and 3 due to the variable binding modes and the specific spatial orientation of the Hbic ligand towards the different paramagnetic metal ions, which were further aggregated into different 3D supramolecular architectures by popular hydrogen‐bonding interactions. Weak and comparable antiferromagnetic couplings mediating by Hbic bridge are observed between the neighboring spin carriers for 2 and 3 , respectively. Additionally, complexes 1 – 3 also display different luminescence emissions at room temperature due to the ligand‐to‐metal charge transfer.  相似文献   

6.
Two coordination polymers, [Co2(Hcpip)2(phth)]n · 3n(H2O) ( 1 ) and [Mn2(Hcpip)2(phth)]n ( 2 ), {H2cpip = 2‐(2‐carboxyphenyl)imidazo[4,5‐f](1,10)‐ phenanthroline, H2phth = phthalic acid}, were hydrothermally synthesized and characterized by elemental analysis, IR spectroscopy, and single‐crystal X‐ray diffraction. Complex 1 is a 1D chain, in which the dinuclear [Co2(Hcpip)2]2+ units are linked through (phth)2– anions. Complex 2 is a 2D layer structure, which is constructed from the 1D chains bridged by (phth)2– anions. The magnetic properties of 1 and 2 show that the weak ferromagnetic interactions occurred between CoII ions in 1 and a weak antiferromagnetic interactions exist between MnII ions in 2 . These two complexes have good thermal stabilities.  相似文献   

7.
Reaction of a imidazole phenol ligand 4‐(imidazlo‐1‐yl)phenol (L) with 3d metal salts afforded four complexes, namely, [Ni(L)6] · (NO3)2 ( 1 ), [Cu(L)4(H2O)] · (NO3)2 · (H2O)5 ( 2 ), [Zn(L)4(H2O)] · (NO3)2 · (H2O) ( 3 ), and [Ag2(L)4] · SO4 ( 4 ). All complexes are composed of monomeric units with diverse coordination arrangements and corresponding anions. All the hydroxyl groups of monomeric cations are used as hydrogen‐bond donors to form O–H ··· O hydrogen bonds. However, the coordination habit of different metal ions produces various supramolecular structures. The NiII atom shows octahedral arrangement in 1 , featuring a 3D twofold inclined interpenetrated network through O–H ··· O hydrogen bond and π–π stacking interaction. The CuII atom of 2 displays square pyramidal environment. The O–H ··· O hydrogen bond from the [Cu(L)4(H2O)]2+ cation and lattice water molecule as well as π–π stacking produce one‐dimensional open channels. NO3 ions and lattice water molecules are located in the channels. 3 is a 3D supramolecular network, in which ZnII has a trigonal bipyramid arrangement. Two different rings intertwined with each other are observed. The AgI in 4 has linear and triangular coordination arrangements. The mononuclear units are assembled into a 1D chain by hydrogen bonding interaction from coordination units and SO42– anions.  相似文献   

8.
Four metal complexes of N,N′-bis(salicyl)-2,6-pyridine-dicarbohydrazide ligand (H6L), [CoII(H4L)(H2O)2]·2DMF (1), [ZnII(H4L)(H2O)2]·2DMF (2), [CdII(H4L)(Py)2]·DMF·Py (3), and [CoIICo2III(H4L)4(H2O)4]·DMF·H2O (4), were synthesized and characterized by elemental analysis, IR, and single-crystal X-ray diffraction analysis. Structural studies revealed that complexes 13 present discrete mononuclear structures and complex 4 displays a centrosymmetric mixed-valence trinuclear structure. All four complexes are further extended into interesting two- or three-dimensional supramolecular frameworks. The luminescent properties of 2 and 3 were studied, which show emissions with maxima at 485 nm upon excitation at 396 nm for 2 and 476 nm upon excitation at 397 nm for 3, respectively.  相似文献   

9.
The imidazole‐based dicarboxylate ligand 2‐(4‐(pyridin‐4‐yl)phenyl)‐1H‐imidazole‐4,5‐dicarboxylic acid (H3PyPhIDC), was synthesized and its coordination chemistry was studied. Solvothermal reactions of CaII, MnII, CoII, and NiII ions with H3PyPhIDC produced four coordination polymers, [Ca(μ3‐HPyPhIDC)(H2O)2]n ( 1 ), {[M32‐H2PyPhIDC)23‐HPyPhIDC)26(H2O)2] · 6H2O}n [M = Mn ( 2 ), Co ( 3 )], and {[Ni(μ3‐HPyPhIDC)(H2O)] · H2O}n ( 4 ). Compounds 1 – 4 were analyzed by IR spectroscopy, elemental analyses, and single‐crystal and powder X‐ray diffraction. Compound 1 displays a one‐dimensional (1D) infinite chain. Compounds 2 and 3 are of similar structure, showing 2D network structures with a (4,4) topology based on trinuclear clusters. Compound 4 has another type of 2D network structure with a 3‐connected (4.82) topology. The results revealed that the structural diversity is attributed to the coordination numbers and geometries of metal ions as well as the coordination modes and conformations of H3PyPhIDC. Moreover, the thermogravimetric analyses of all the compounds as well as luminescence properties of the H3PyPhIDC ligand and compound 1 were also studied.  相似文献   

10.
The use of pyridine‐2,4‐dicarboxylic acid (H2pydc) in the construction of SrII and SrII‐MII (M=Co, Ni, Zn and Cu) coordination polymers is reported. Eight complexes, that is, [Sr(pydc)H2O]n ( 1 ), [MSr(pydc)2(H2O)2]n (M=Co ( 2 ), Ni ( 3 ), Zn ( 4 )), [ZnSr(pydc)2(H2O)7]n?4 nH2O ( 5 ), [SrCu(pydc)2]n ( 6 ), [SrCu(pydc)2(H2O)3]n?2 nH2O ( 7 ), and [Cu3Sr2(pydc)4(Hpydc)2(H2O)2]n ( 8 ), have been synthesized via dexterously choosing the appropriate strontium sources and transition metal salts, and rationally controlling the temperature of the reaction systems. Complexes 1 , 2 ( 3 , 4 ), 6 , and 8 display four types of 3‐D framework structures. Complexes 5 and 7 exhibit a 2‐D network and a 1‐D chain structure, respectively. The 2‐D complex 7 can be reversibly transformed into 3‐D compound 6 through temperature‐induced solvent‐mediated structural transformation. The luminescent property studies indicated that complex 1 shows a strong purple luminescent emission and 4 exhibits a strong violet luminescence emission. The magnetic properties of 2 , 3 , and 8 were also studied. Antiferromagnetic MII???MII interactions were determined for these complexes.  相似文献   

11.
Two new nickel(II) complexes, [Ni(4, 4′‐bpy)(H2O)4]n · n(cpp) · 0.5nH2O ( 1 ) and [Ni(cpp)(4, 4′‐bpy)(H2O)2]n ( 2 ) [4, 4′‐bpy = 4, 4′‐bipyridine, H2cpp = 3‐(4‐carboxyphenyl)propionic acid] were synthesized and characterized by single‐crystal X‐ray diffraction, elemental analysis, IR spectroscopy, and thermal analysis. In complex 1 , NiII ions are bridged by 4, 4′‐bpy into 1D chains, and cpp ligands are not involved in the coordination, whereas in complex 2 , cpp ligands adopt a bis(monodentate) mode and link NiII ions into 2D (4, 4) grids with the help of 4, 4′‐bpy ligands. Triple interpenetration occurs, which results in the formation of a complicated 3D network. The difference in the structures of the two complexes can be attributed to the different reaction temperatures and bases.  相似文献   

12.
Four CuII and CoII complexes–[Cu(L1)Cl2(H2O)]3/2H2O · 1/2EtOH, [Cu(L1)2Cl2]6H2O, [Co(L1)Cl2]3H2O · EtOH, and [Co2(L1)(H2O)Cl4]1.5H2O · EtOH (L1 = 2,4,6-tri(2-pyridyl)-1,3,5-triazine; TPT)–were synthesized by conventional chemical method and used to synthesize another four metal complexes–[Cu(L1)I2(H2O)]6H2O, [Cu(L1)2I2]6H2O, [Co(L1)I(H2O)2]I · 2H2O, and [Co2(L1)I4(H2O)3]–using tribochemical reaction, by grinding it with KI. Substitution of chloride by iodide occurred, but no reduction for CuII or oxidation of CoII. Oxidation of CoII to CoIII complexes was only observed on the dissolution of CoII complexes in d6-DMSO in air while warming. The isolated solid complexes (CuII and CoII) have been characterized by elemental analyses, conductivities, spectral (IR, UV-Vis, 1H-NMR), thermal measurements (TGA), and magnetic measurements. The values of molar conductivities suggest non-electrolytes in DMF. The metal complexes are paramagnetic. IR spectra indicate that TPT is tridentate coordinating via the two pyridyl nitrogens and one triazine nitrogen forming two five-membered rings around the metal in M : L complexes and bidentate via one triazine nitrogen and one pyridyl nitrogen in ML2 complexes. In binuclear complexes, L is tridentate toward one CoII and bidentate toward the second CoII in [Co2(L1)Cl4]2.5H2O · EtOH and [Co2(L1)I4(H2O)3]. Electronic spectra and magnetic measurements suggest a distorted-octahedral around CuII and high-spin octahedral and square-pyramidal geometry around CoII.  相似文献   

13.
Four novel mixed‐ligand complexes were obtained from the reaction of maleic acid, diimine chelating ligands and Cd(OH)2 or CdO in a mixed solvent of water and methanol. The complexes were characterized by IR spectroscopy, elemental analysis, and single‐crystal X‐ray diffraction. The results show that all the four complexes are coordination polymers. [Cd(phen)(H2O)(male)]n · 2nH2O ( 1 ) and [Cd(bipy)(H2O)(male)]n · 2nH2O ( 2 ) (male = maleate; phen = 1, 10‐phenanthroline, bipy = 2, 2′‐bipyridine) are isomorphic, and the asymmetric unit is constructed by one CdII atom, a maleate group, a diimine ligand and two crystal water molecules. Each maleate group links two CdII atoms in a bis(bidentate) chelating mode, resulting in a 1D helical chain. Within [Cd(phen)(H2O)2(male)]n · 2nH2O ( 3 ), the maleate group bridges two CdII atoms in a bis(monodentate) chelating mode into a 1D helical chain along the [100] direction. The helical chain is decorated by phen groups alternatively at the two sides, and each phen plane of one chain is inserted in the void space between two adjacent phen ligands from an adjacent chain, resulting in a double zipper‐like chain. The asymmetric unit of [Cd2(phen)2(male)2]n ( 4 ) contains a CdII cation, one phen molecule, and a maleate group, and one bridging maleate group links three CdII atoms resulting in a 2D layer extending in [011] plane. The 2D networks are constructed by four kinds of rings formed by the central metal atom and maleate dianion. The thermostabilities of the four complexes were investigated.  相似文献   

14.
Three mixed-ligand transition metal coordination polymers with the formula of {[CuI2CuII(tpt)2(L)] · 15H2O}n ( 1 ) and {[M2(H2O)5(tpt)(L)] · 6H2O}n [M = Ni for 2 and Co for 3 ; tpt = 2,4,6-tris(4-pyridyl)-1,3,5-triazine and L = 3,3'-disulfonyl-4,4'-biphenyldicarboxylate] were hydrothermally synthesized by varying the cheap paramagnetic metal ions and used as photocatalysts for hydrogen evolution from water splitting and rhodamine B (RhB) degradation. Single-crystal structural determinations reveal that 1 is a robust pillared-layer framework with unusual 72-membered {Cu6(tpt)6} macrocycle-based layers supported by tetratopic L4– connectors. Both 2 and 3 are isostructural (4 4) sheets with octahedral NiII and CoII ions extended by ditopic L4– and tpt linkages, in which the third pyridyl group of tpt is capped by pentahydrated metal ions. Due to the narrowed bandgap and good charge transport of the mixed-valence CuI/II centers, 1 exhibits improved dual-functional catalytic activities than 2 and 3 with the visible-light-driven hydrogen evolution rate and RhB degradation efficiency up to 588 μmol · g–1 · h–1 and 72 % after 180-minute irradiation. These interesting results indicate the importance of the metal ions and the dimensionality of the coordination polymers on the activity of the non-Pt coordination polymer photocatalytic systems.  相似文献   

15.
By using cyclohexane‐1,2‐diamine (chxn), Ni(ClO4)2 ? 6H2O and Na3[Mo(CN)8] ? 4H2O, a 3D diamond‐like polymer {[NiII(chxn)2]2[MoIV(CN)8] ? 8H2O}n ( 1 ) was synthesised, whereas the reaction of chxn and Cu(ClO4)2 ? 6H2O with Na3[MV(CN)8] ? 4H2O (M=Mo, W) afforded two isomorphous graphite‐like complexes {[CuII(chxn)2]3[MoV(CN)8]2 ? 2H2O}n ( 2 ) and {[CuII(chxn)2]3[WV(CN)8]2 ? 2H2O}n ( 3 ). When the same synthetic procedure was employed, but replacing Na3[Mo(CN)8] ? 4H2O by (Bu3NH)3[Mo(CN)8] ? 4H2O (Bu3N=tributylamine), {[CuII(chxn)2MoIV(CN)8][CuII(chxn)2] ? 2H2O}n ( 4 ) was obtained. Single‐crystal X‐ray diffraction analyses showed that the framework of 4 is similar to 2 and 3 , except that a discrete [Cu(chxn)2]2+ moiety in 4 possesses large channels of parallel adjacent layers. The experimental results showed that in this system, the diamond‐ or graphite‐like framework was strongly influenced by the inducement of metal ions. The magnetic properties illustrate that the diamagnetic [MoIV(CN)8] bridges mediate very weak antiferromagnetic coupling between the NiII ions in 1 , but lead to the paramagnetic behaviour in 4 because [MoIV(CN)8] weakly coordinates to the CuII ions. The magnetic investigations of 2 and 3 indicate the presence of ferromagnetic coupling between the CuII and WV/MoV ions, and the more diffuse 5d orbitals lead to a stronger magnetic coupling interaction between the WV and CuII ions than between the MoV and CuII ions.  相似文献   

16.
Reaction of Mn(NCS)2 with 4-picoline (4-methylpyridine) leads to the formation of [Mn(NCS)2(4-picoline)4] · 0.67 · 4-picoline · 0.33 · H2O ( 1 - Mn ) reported in literature, Mn(NCS)2(4-picoline)2(H2O)2 ( 2-Mn/H2O ), and of [Mn(NCS)2(4-picoline)2]n ( 2-Mn/I ). 1-Mn and 2-Mn/H2O consist of discrete complexes, in which the metal cations are octahedrally coordinated, whereas in 2-Mn/I the metal cations are linked by pairs of μ-1,3-bridging thiocyanate anions into corrugated chains. Measurements using thermogravimetry and differential scanning calorimetry as well as temperature dependent X-ray powder diffraction on 1-Mn and 2-Mn/H2O reveal that upon heating both compounds transform into [Mn(NCS)2(4-picoline)]n ( 3-Mn ) via 2-Mn/I as intermediate. 3-Mn shows a very rare chain topology in which the metal cations are linked by μ-1,3,3 (N,S,S) coordinating anionic ligands which was never observed before with MnII. From these investigations there is no hint that a further modification of 2-Mn can be prepared as recently observed for [M(NCS)2(4-picoline)2]n (M = Fe, Cd) and such a form is also not available if the metastable forms of the FeII or CdII compounds were used as template during thermal decomposition. Magnetic investigations on 2-Mn/H2O show only paramagnetic behavior, whereas for 2-Mn/I antiferromagnetic ordering is observed. Finally, the crystal structure of Mn(NCS)2 was determined from XRPD data, which shows that it is strongly related to that of 3-Mn .  相似文献   

17.
Two new ZnII coordination polymers (CPs), [Zn2(SA)2(L)2]n ( 1 ) and [Zn(AA)(L)]n ( 2 ) [L = 1,6‐bis(benzimidazol‐1‐yl)hexane, H2SA = succinic acid, H2AA = adipic acid], were synthesized via hydrothermal method and characterized by elemental analysis, infrared spectroscopy, and single‐crystal X‐ray diffraction. CP 1 possesses a sql network, which is further extended into a 3D supramolecular skeleton by non‐classical C–H ··· O hydrogen bonding interactions. CP 2 exhibits a 1D linear chain, which is further assembled into a 2D supramolecular layer by π ··· π stacking interactions. The solid state fluorescence properties of two ZnII CPs were investigated. Both CPs present high photocatalytic activities for the degradation of methylene blue (MB) under UV light irradiation. The photodegradation efficiency using CP 1 as catalyst is 91.3 % and using CP 2 as catalyst is 85.0 %, respectively.  相似文献   

18.
Two tosylated isophthalic ligands, namely, 5‐tosyloxy‐isophthalic acid (H2toip) and 5‐tosylamino‐isophthalic acid (H2taip) were synthesized. Self‐assembly of CuII ions with H2toip and H2taip ligands under different reaction conditions (temperature, solvents, and auxiliary ligands) gave rise to three coordination polymers formulated as [Cu(toip)(py)2]n ( 1 ), [Cu6(toip)6(H2O)6]n · 8n(H2O) ( 2 ), and [Cu6(taip)6(py)4(dmf)2]n · n[(dmf)6(MeOH)2(H2O)2] ( 3 ) (py = pyridine, dmf = dimethylformamide). Compound 1 is a one‐dimensional (1D) coordination polymeric chain. Compounds 2 and 3 are two‐dimensional (2D) coordination networks featuring very similar Kagomé lattices based on the interconnection of paddle‐wheel [Cu2(COO)4] secondary building units (SBUs) and toip2–/taip2– ligands. However, the arrangement of adjacent Kagomé lattices in 2 and 3 are distinct, making them crystallize in different space groups and thereby have different crystal structures.  相似文献   

19.
Three new coordination compounds, [Pb(HBDC‐I4)2(DMF)4]( 1 ) and [M(BDC‐I4)(MeOH)2(DMF)2]n (M = ZnII for 2 and MnII for ( 3 ) (H2BDC‐I4 = 2, 3, 5, 6‐tetraiodo‐1, 4‐benzenedicarboxylic acid), were synthesized and characterized by elemental analysis, IR spectroscopy, thermogravimetric (TG) analysis, and X‐ray single crystal structure analysis. Single‐crystal X‐ray diffraction reveals that 1 crystallizes in the monoclinic space group C2/c and has a discrete mononuclear structure, which is further assembled to form a two‐dimensional (2D) layer through intermolecular O–H ··· O and C–H ··· O hydrogen bonding interactions. The isostructural compounds 2 and 3 crystallize in the space group P21/c and have similar one‐dimensional (1D) chain structures that are extended into three‐dimensional (3D) supramolecular networks by interchain C–H ··· π interactions. The PbII and ZnII complexes 1 and 2 display similar emissions at 472 nm in the solid state, which essentially are intraligand transitions.  相似文献   

20.
The Crystal Structure of the Hydrated Cyano Complexes NMe4MnII[(Mn, Cr)III(CN)6] · 3 H2O and NMe4Cd[MIII(CN)6] · 3 H2O (MIII = Fe, Co): Compounds Related to Prussian Blue The crystal structures of the isotypic tetragonal compounds (space group I4, Z = 10) NMe4MnII · [(Mn, Cr)III(CN)6] · 3 H2O (a = 1653.2(4), c = 1728.8(6) pm), NMe4Cd[Fe(CN)6] · 3 H2O (a = 1642.7(1), c = 1733.1(1) pm) and NMe4Cd[Co(CN)6] · 3 H2O (a = 1632.1(2), c = 1722.4(3) pm) were determined by X‐rays. They exhibit ⊥ c cyanobridged layers of octahedra [MIII(CN)6] and [MIIN4(OH2)2], which punctually are interconnected also || c to yield altogether a spaceous framework. The MII atoms at the positions linking into the third dimension are only five‐coordinated and form square pyramids [MIIN5] with angles N–MII–N near 104° and distances of Mn–N: 1 × 214, 4 × 219 pm; Cd–N: 1 × 220 resp. 222, 4 × 226 resp. 228 pm. Further details and structural relations within the family of Prussian Blue are reported and discussed.  相似文献   

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