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1.
Three novel N,N′-bis(2-hydroxy-3-methoxybenzylidene)-1,3-diaminopropane dimeric lanthanide complexes, namely, [{H2L}Sm(NO3)3]2·H2O (1), [{H2L}Gd(NO3)3]4·CH3OH (2), [{H2L}Lu(NO3)3]4·H2O (3) (H2L = N,N′-bis(2-hydroxy-3-methoxybenzylidene)-1,3-diaminopropane) and three new N,N′-bis(2-hydroxy-3-methoxybenzylidene)-1,3-diaminopropane 3d-Gd heterodinuclear complexes, namely, [{LCo}(CH3COO)(CH3COOH)Gd(NO3)2] (4), [{LNi(MeOH)2}Gd(NO3)3]·2MeOH (5) and [{(L)Zn(HNO3)}Gd(NO3)3]·NO3·H3O·MeOH (6) have been synthesized and isolated. X-ray crystallographical analysis reveals that complexes 1-3 are isomorphic with unique dimeric topology. Complexes 4-6 are of discrete 3d-4f dinuclear cores. Magnetic properties of complexes 2 and 4-6 are systematically investigated. Complexes 4 and 5 are ferromagnetic, while 2 and 6 are antiferromagnetic.  相似文献   

2.
Two new zinc phosphonates with 2-hydroxyphosphonoacetic acid (HPAA) and 1-hydroxyethylidenediphosphonic acid (hedpH4), [Zn2{HO3PCH(OH)CO2}3]·2NH2(CH3)2·3H2O (1) and [Zn3{CH3C(OH)(PO3)2}2]·2NH2(CH3)2·H2O (2) have been synthesized under mixed-solvothermal conditions at 160 °C and structurally characterized by X-ray single-crystal diffraction, X-ray powder diffraction, infrared spectroscopy and elemental analysis. The structure of compound 1 comprises Zn1O6 and Zn2O6 octahedra connected by [HO3PCH(OH)CO2]2− to form a 2D layered structure with one-dimensional channel system along c-axis direction, and the protonated dimethylamine cations are being located between two adjacent layers. Interestingly the layers of 1 arranged in an alternative sequence (ABAB). Compound 2 features a 3D framework structure with channels along the b- and c-axis, respectively. The charge-compensating protonated Hdma+ cations and solvate water molecules are located inside the channels along the c-axis. A notable feature for compound 2 is the presence of the alternate left- and right-handed helical chains in the structure. The luminescence properties of compounds 1 and 2 have also been studied.  相似文献   

3.
New trinuclear iron(III) furoates with the general formula [Fe3O(α-fur)6(R-OH)3]X, where α-fur C4H3OCOO, R = CH3 (1), C2H5 (2), n-C3H7 (3), n-C4H9 (4), X = NO3 (1-4); [Fe3O(α-Fur)6(DMF)(CH3OH)2]NO3 (5); [Fe3O(α-Fur)6(H2O)(CH3OH)2]Cl (6); [Fe2MO(α-Fur)6(L)(H2O)2], where L = THF (7-9), DMF (10-12), M = Mn2+ (7, 10), Co2+ (8, 11), Ni2+ (9, 12) and [Fe2MO(α-Fur)6(3Cl-Py)3], where M = Mn2+ (13), Co2+ (14), Ni2+ (15); have been prepared and investigated by Mössbauer and IR spectroscopy. The X-ray crystal structure for the 1·2CH3OH complex indicates that it crystallizes in the monoclinic crystal system (P21/n) and has a structure typical of μ3-O-bridged trinuclear iron(III) compounds. Coordination compounds 1, 4, 7, 8 can be used as regulators of the biochemical composition of cyanobacterium Spirulina platensis biomass. The supplementation of these compounds, in concentrations exceeding 5-10 mg/l, increases the content of iron, amino acids, peptides and carbohydrates in Spirulina.  相似文献   

4.
Four MnIII quadridentate Schiff-base compounds have been prepared and structurally characterized: [Mn(salpn)(CH3OH)2]BPh4 (1), [Mn2(salpn)2(N3)2] (2), [Mn2(salpn)2(NCS)2] (3), [Mn2(salpn)2(H2O)2](H2O)(ClO4)2 (4) (salpn = N,N′-(1,2-propylene)-bis-(salicylideneiminate)). Among them, 1 is a discrete MnIII monomeric complex with a square-bipyramidal geometry. Complexes 2, 3 and 4 form the similar phenolate-bridged out-of-plane dimers. Magnetic susceptibility studies reveal that 2, 3 and 4 all exhibit ferromagnetic intra-dimer coupling between MnIII ions.  相似文献   

5.
Five novel heterometallic Ni/Zn coordination compounds [Ni(en)3][ZnCl4] (1), [Ni(en)(Hea)2][ZnCl4] (2), [Ni(dien)2][ZnCl4] (3), [Ni(en)3][ZnCl4] · 2DMSO (4) and [Ni(en)3][Zn(NCS)4] · CH3CN (5), where en = ethylenediamine (ethane-1,2-diamine), Hea = monoethanolamine (2-aminoethanol) and dien = diethylenetriamine (1,4,7-triazaheptane), have been synthesized by means of the open-air reaction of zinc oxide, nickel chloride (or nickel powder), NH4X (X = Cl, NCS) and ligand (en, dien, Hea) in non-aqueous solvents, such as DMSO, DMF, CH3OH and CH3CN. The choice of a counter-anion in the initial ammonium salt as well as selection of the ligand and solvent provides an effortless approach to the controlled assembly of two- or three-dimensional extended networks assisted by hydrogen bonding. Crystallographic investigations reveal that 1, 2 and 5 possess 3D, while 3 and 4 exhibit 2D H-bonded crystal structures. The structures of the compounds exhibit six-coordinated Ni(II) centers and four-coordinated Zn(II) centers in distorted octahedral and tetrahedral geometries, respectively.  相似文献   

6.
The Schiff base ligands 2-(2,6-diisopropylphenyliminomethyl)phenol H(L1), 5-diethylamino-2-(2,6-diisopropylphenyliminomethyl)phenol H(L2), 2,4-di-tert-butyl-6-(2,6-diisopropylphenyliminomethyl)phenol H(L3), 3-(2,6-diisopropylphenyliminomethyl)naphthalen-2-ol H(L4) and 4-(2,6-diisopropylphenyliminomethyl)-5-hydroxymethyl-2-methylpyridin-3-ol H(L5) have been synthesized by the condensation, respectively, of salicylaldehyde, 4-(diethylamino)salicylaldehyde, 3,5-di-tert-butylsalicylaldehyde, 2-hydroxy-1-napthaldehyde and pyridoxal with 2,6-diisopropylaniline. The copper(II) bis-ligand complexes [Cu(L1)2] 1, [Cu(L2)2] 2, [Cu(L3)2] 3, [Cu(L4)2] 4 and [Cu(L5)2] · CH3OH 5 of these ligands have been isolated and characterized. The X-ray crystal structures of two of the complexes [Cu(L1)2] 1 and [Cu(L5)2] · CH3OH 5 have been successfully determined, and the centrosymmetric complexes possess a CuN2O2 chromophore with square planar coordination geometry. The frozen solution EPR spectra of the complexes reveal a square-based CuN2O2 chromophore, and the values of g and g/A index reveal enhanced electron delocalization by incorporating the strongly electron-releasing -NEt2 group (2) and fusing a benzene ring on sal-ring (4). The Cu(II)/Cu(I) redox potentials of the Cu(II) complexes reveal that the incorporation of electron-releasing -NEt2 group and fusion of a benzene ring lead to enhanced stabilization of Cu(II) oxidation state supporting the EPR spectral results. The hydrogen bonding interactions between the two molecules present in the unit cell of 5a generate an interesting two-dimensional hydrogen-bonded network topology.  相似文献   

7.
Three new complexes, [Zn(PPePeP-PNH)(CH3OH)]2(CH3OH) [PPePeP-PHN = N-(1-phenyl-3-phenylethyl-4-phenylethylene-5-pyrazolone) p-nitrobenzoylhydrazide] (1), [Mn(PPePeP-PNH)(CH3OH)2]2(CH3OH) (2), [Mn(PM4MbP-PNH)(C2H5OH)3] [PM4MbP-PHN = N-(1-phenyl-3-methyl-4-(p-methylbenzoylene)-5-pyrazolone) p-nitrobenzoylhydrazide] (3), have been prepared and characterized by elemental analyses, IR spectra, UV-Vis absorption spectra, thermal-analyses and X-ray diffraction studies. The structural analyses show that the N(2) atoms of the pyrazolyl heterocycles play an important role in building the N-H?O hydrogen bonds of 1, 2, 3 and 1, 2 formed 2D networks and 3 formed 1D chain linked by hydrogen bonds, respectively.  相似文献   

8.
《Inorganica chimica acta》2004,357(5):1444-1456
The complexes cis-[PdCl22-[C(H)PH3]2CO}] (2) in two different stereochemical arrangements (cisoid-cisoid, 2cc; cisoid-transoid, 2ct) have been studied by DFT methods at the B3LYP level. The (2cc) structure is energetically more stable than the (2ct), being the main responsible of the energy difference between the two complexes the energetic gap between the cc and ct isomers of the free bis-ylide ligand [H3PC(H)-C(O)-C(H)PH3] (1). In (1) these differences arise from the presence of 1,4-intramolecular interactions between the phosphorus atoms and the carbonyl oxygen. That is, the conformational preferences observed in (1) due to the establishment of 1,4-P?O interactions are directly transferred to the metallic complexes (2) in such a way that the most stable structure for the free ligand gives the most stable complex. In the absence of the carbonyl group (e.g. [H3PC(H)-C(CH2)-C(H)PH3] (3) or [H3PC(H)-CH2-C(H)PH3] (5)) all isomers of a given bis-ylide (cc, ct and tt) become isoenergetic. The absence of discrimination in the free bis-ylides (3) and (5) gives isoenergetic cc and ct structures for the corresponding complexes cis-[PdCl22-[C(H)PH3]2CCH2}] (4), cis-[PdCl22-[C(H)PH3]2CH2}] (6) and [CpNi{η2-[C(H)PH3]2CH2}] (7), as stated by NMR spectroscopy for (7). The influence of other factors (change of the heteroatom at Cβ, change of the P substituents) in the energy of the different isomers of the bis-ylides and in the energy of the corresponding complexes has also been studied and discussed.  相似文献   

9.
Three complexes of composition [Co2IICo2III(H2hbhpd)2(H4hbhpd)2(H2O)2]Cl2(CH3OH)4 (1), [Co2IICo2III(H2hbhpd)2(H4hbhpd)2(H2O)2](NO3)2(CH3OH)4 (2) and [Ni2(H4hbhpd)2(NO3)](NO3)(CH3OH)1.5 (3) (H5hbhpd = 2-(2-hydroxy-benzylamino)-2-hydroxymethyl-propane-1,3-diol) have been synthesized and their structures have been characterized. Complexes 1 and 2 are mixed-valence cobalt clusters and display face-sharing monovacant dicubane structures. In the complexes 1 and 2, one of the three alkyl hydroxyl groups of H5hbhpd ligand is deprotonated instead of deprotonation of phenyl hydroxyl group; thus monoanionic H4hbhpd ligand displays novel η3, η1, η1, μ3 coordination mode. Complex 3 is binuclear, and the two metal centers of 3 are bridged by two deprotonated phenyl hydroxyl oxygen atoms and iso-orthogonalized by a nitrato group in η1η1-O,O′ coordination fashion. Variable-temperature solid-state dc magnetization studies have been performed in the temperature range 2-300 K for compounds 1 and 3. Antiferromagnetic interactions were determined for 1 and ferromagnetic couplings were found for 3.  相似文献   

10.
The dinuclear and trinuclear copper(II) complexes [Cu2(L)(OH)(ClO4)(phen)(H2O)]ClO4 · [Cu2(L)(OH)(ClO4)2(phen)(CH3OH)] (1) and [Cu3(L)2(OH)2(H2O)2](NO3)2 (2) (HL=2-[2-(α-pyridyl)ethyl]imino-3-butanone oxime and phen=1,10-phenanthroline) were prepared and their crystal structures have been determined by X-ray crystallography. Complex 1 is composed of [Cu2(L)(OH)(ClO4)(phen)(H2O)]ClO4 (1a) and [Cu2(L)(OH)(ClO4)2(phen)(CH3OH)] (1b). In 1a and 1b, one oximato of L and one hydroxo group bridge two copper(II) ions. The linear trinuclear cation [Cu3(L)2(OH)2(H2O)2]2+ in 2 is centrosymmetric, and one oximato and one hydroxo group bridge the central and terminal copper(II) ions. The strong antiferromagnetic interactions within the dinuclear and trinuclear complexes 1 and 2 have been observed (2J=∼−900 cm−1 for 1 and 2, respectively, H=−2JS1·S2).  相似文献   

11.
Three distinct coordination complexes, viz. {[Cu(μ-L)2] · (H2O)4}n (1), [Ni(L)2(CH3OH)2] (2), and [Zn(L)2(H2O)2] · (H2O)2 (3), have been prepared by the reactions of metal nitrates with isoquinoline-3-carboxylic acid (HL). X-ray single-crystal diffraction suggests that 1 is a 1D chain coordination polymer in which the CuII ions are connected by carboxylates, whereas complexes 2 and 3 represent discrete mononuclear species. In all the cases, the coordination entities are further organized via hydrogen-bonding interactions to generate multifarious supramolecular networks. Remarkably, a well-resolved 1D water morphology is observed for the first time in the crystalline lattice of 1 along [1 0 0], which consists of edge-sharing tetrameric subunits and stabilized by the metal-organic host surroundings.  相似文献   

12.
The macrocyclisation reaction of 3,3′-(3,6-dioxaoctane-1,8-diyldioxy)-bis(2-hydroxybenzaldehyde) (1) with S-methylisothiosemicarbazide hydroiodide (H2NNC(SCH3)NH2·HI) in the presence of potassium triflate, followed by addition of M(CH3COO)2·nH2O, where M=Ni, Cu, Zn, afforded [NiLKI3] (2), [NiLK(CF3SO3)] (3), [CuLK(CF3SO3)(CH3OH)] (4) and [(ZnILK)2CH3OH] (5), respectively. Compounds 2-5 have been characterised by X-ray crystallography. IR, electronic, mass, 1H, 13C{1H} and 19F{1H} NMR spectra are reported. Magnetic susceptibility measurements and ESR spectra of 4 indicate weak intermolecular spin-spin interactions, which are mostly dipolar in origin.  相似文献   

13.
Two new dinuclear isophthalato-bridged copper(II) complexes [Cu2(ntb)2(μ-ipt)](ClO4)2·4CH3OH·0.33H2O (1), [Cu2(bbma)2(μ-ipt)(NO3)(CH3OH)]NO3·CH3OH (2) and one mononuclear complex [Cu(bbma)(ipt)(CH3OH)0.67(H2O)0.33]·2CH3OH (3) containing tetradentate and tridentate poly-benzimidazole ligands were synthesized, where ntb is tris(2-benzimidazolylmethyl)amine, bbma is bis(benzimidazol-2-yl-methyl)amine and ipt is isophthalate dianion. All of the complexes were characterized by elemental analysis, IR spectra and X-ray crystallography. The structures of complexes 1 and 2 consist of μ-ipt bridging two Cu(II) centers in a bis(monodentate) bonding fashion. The coordination geometry around the Cu(II) ions of both compounds has a distorted square pyramidal geometry. The Cu···Cu distances are 9.142 and 10.435 Å for 1 and 2, respectively. Complex 3 has a distorted square pyramidal geometry achieved by the three N-atoms of the bbma ligand, one isophthalate-oxygen atom and one oxygen atom from a coordinated methanol molecule. The magnetic susceptibility measurements at variable temperature over the 2-300 K range for complexes 1 and 2 are reported, with J values to be −0.013 and −0.32 cm−1, respectively. The results show that the two complexes exhibit very weak antiferromagnetic interactions between the dinuclear copper(II) centers.  相似文献   

14.
A new series of biscyclometalated dinuclear rhodium (II) compounds with the general formula Rh2(O2CR)2(PC)2 · 2H2O, being PC = (C6H4)P(C6H5)2, R = CH3 (1 · 2H2O), PC = [(p-CH3 OC6H3)P(p-CH3 OC6H4)2], R = CF3 (2 · 2H2O), PC = (C6H4)P[CH(CH3)2]2, R = CH3 (3 · 2H2O) and PC = (C6H4)P(C6H5)2, R = C6F5 (4 · 2H2O) has been obtained. The crystal structures for these compounds have been determined by X-ray diffraction and the main structural trends, bond lengths, bond angles and torsion angles have been analyzed, and have also been compared with the structural parameters for different analogous complexes described previously in the literature.  相似文献   

15.
Reaction of vanadium(III) chloride with 8-quinolinol (Hqn) gave a mononuclear vanadium(IV) complex, [VOCl2(H2O)2] 1) · 2H2qn · 2Cl · CH3CN, and three dinuclear vanadium(IV) complexes: [V2O2Cl2(qn)2(H2O)2] (2) · Hqn, [V2O2Cl2(qn)2(C3H7OH)2] (3), and [V2O2Cl2(qn)2(C4H9OH)2] (4). Reaction of vanadium(III) chloride with 5-chloro-8-quinolinol (HClqn) gave four dinuclear vanadium(IV) complexes: [V2O2Cl2(Clqn)2(H2O)2] (5) · 2HClqn, [V2O2Cl2(Clqn)2(C3H7OH)2] (6), [V2O2Cl2(Clqn)2(C6H5CH2OH)2] (7), and [V2O2Cl2(Clqn)2(C4H9OH)2] (8) · 2C4H9OH. Reaction of vanadium(III) chloride with 5-fluoro-8-quinolinol (HFqn) gave two dinuclear vanadium(IV) complexes: [V2O2Cl2(Fqn)2(H2O)2] (9) · HFqn · 2H2O and V2O2Cl2(Fqn)2(C3H7OH)2] (10). X-ray structures of 1 · 2H2qn · 2Cl · CH3CN, 3, 4, 6, 7, 8 · 2 t-BuOH, and 10 have been determined. As to the mononuclear species 1 · 2H2qn · 2Cl · CH3CN, coordination of Hqn to vanadium does not occur, but protonation to Hqn occurs to give H2qn+, which links 1’s through hydrogen bonding, while each of the dinuclear species has a terminal and a bridging qn (or Clqn, Fqn) ligand, giving rise to a (V-O)2 ring. Magnetic measurements of 3, 4, 6, 7, and 10 in solid form show very weak antiferromagnetic behavior, and the effective magnetic moments are close to spin only value (2.44) of d1-d1 system, while ESR of 3 in THF shows dissociation to monomeric species. Change from mononuclear, 1, to dinuclear, 2, species was followed by the change of electronic spectrum.  相似文献   

16.
Novel titanocanes and spirobititanocanes based on 2,6-bis[hydroxy(diphenyl)methyl]pyridine (1a) and 2,6-di(hydroxymethyl)pyridine (1b) - [2,6-C5H3N(CPh2O)2]Ti(O-i-Pr)2 (2a), [2,6-C5H3N(CPh2O)2]2Ti (3a), [2,6-C5H3N(CH2O)2]2Ti (3b), [2,6-C5H3N(CPh2O)2]TiCl2 (4) - as well as the closely related N-phenyl derivative PhN(CH2CH2O)2Ti(Cl)Cp (5) have been synthesized. Complexes 2-5 were characterized by 1H and 13C NMR spectroscopy and elemental analysis data. The molecular structure of 3a was determined by X-ray structure analysis.  相似文献   

17.
The solvatothermal reactions of V2O5, the appropriate organoamine and HF in the temperature range 100-180 °C yielded a series of vanadium fluorides and oxyfluorides. The compounds [NH4][H3N(CH2)2NH3][VF6] (1) and [H3N(CH2)2NH3][VF5(H2O)] (2) contain mononuclear V(III) anions, while [H3N(CH2)2NH2(CH2)2NH3]2 [VF5(H2O)]2[VOF4(H2O)] (3) exhibits both V(IV) and V(III) mononuclear anions. Both compound 4, [H3NCH2(C6H4)CH2NH3][VOF4]·H2O (4·H2O) and compound 5, [HN(C2H4)3NH][V2O2F6 (H2O)2] (5) contain binuclear anions constructed from edge-sharing V(IV) octahedra. In contrast, [H3N(CH2)2NH2(CH2)2NH3]2[V4O4F14(H2O)2], (6) exhibits a tetranuclear unit of edge- and corner-sharing V(IV) octahedra. Compound 7, [H3N(CH2)2NH2][VF5], contains chains of corner-sharing {VIVF6} octahedra, while [H2N(C2H4)2NH2]3[V4F17O]·1.5H2O (8·1.5H2O) is two-dimensional with a layer of V(III) and V(IV) octahedra in an edge- and corner-sharing arrangement. In the case of [H3N(CH2)2NH3][V2O6] (9), there was no fluoride incorporation, and the anion is a one-dimensional chain of corner-sharing V(V) tetrahedra.  相似文献   

18.
Two new zincophosphites [C6H14N2]0.5[Zn(H2PO3)2] 1 and [C4H12N2]0.5[(CH3)2NH2][Zn2(HPO3)3] 2 have been solvothermally synthesized in mixed solvents of N,N-dimethylformamide (DMF) and 1,4-dioxane (DOA), respectively. Single-crystal X-ray diffraction analysis reveals that compound 1 exhibits a neutral inorganic chain formed by ZnO4 and HPO2(OH) units. Interestingly, the left- and right-handed hydrogen-bonded helical chains are alternately formed via the hydrogen-bonds between two adjacent chains. Compound 2 exhibits a layer structure with 4- and 12-MRs formed by ZnO4 and HPO3 units, in which two kinds of organic amine molecules both act as countercations to compensate the overall negative electrostatic charge of the anionic network.  相似文献   

19.
Four one-dimensional metal-organic polymers derived from diphenic acid (H2dpa) were synthesized in the presence of auxiliary ligands, [Cu(dpa)CH3OH](1), [Ni(dpa)CH3OH] (2), [Cu(bipy)2(Hdpa)2(H2O)2] (3) and [Ni(bipy)2(Hdpa)2(H2O)2] (4) (bipy = 4, 4′-bipyridine). The dinuclear paddle-wheel second building units (SBUs) constructed by four dpa2− ligands in complexes 1 and 2 are linked by dpa2− into double chains, which are connected by C-H?π interactions forming a two-dimensional rhombic porous structure. In complexes 3 and 4, the metal ions are connected by bipy ligands, and the grid-like network was formed with the π-π interactions between the adjacent phenyl rings of Hdpa. For 1 and 2, there are strong antiferromagnetic interactions within Cu-Cu and Ni-Ni dimers. It is also strong antiferromagnetic interactions between the dimmers of Cu2 in 1, while it is weaker of those of Ni2 in 2. Weaker antiferromagnetic interactions exist among Cu-Cu and Ni-Ni in 3 and 4, in which bipy is the effective coupling media. Thermally gravimetric analyses and differential thermal analyses indicate that the four complexes are all thermal stable.  相似文献   

20.
Reaction of the potassium salts of (EtO)2P(O)CH2C6H4-4-(NHC(S)NHP(S)(OiPr)2) (HLI), (CH2NHC(S)NHP(S)(OiPr)2)2 (H2LII) or cyclam(C(S)NHP(S)(OiPr)2)4 (H4LIII) with [Cu(PPh3)3I] or a mixture of CuI and Ph2P(CH2)1-3PPh2 or Ph2P(C5H4FeC5H4)PPh2 in aqueous EtOH/CH2Cl2 leads to [Cu(PPh3)LI] (1), [Cu2(Ph2PCH2PPh2)2LII] (2), [Cu{Ph2P(CH2)2PPh2}LI] (3), [Cu{Ph2P(CH2)3PPh2}LI] (4), [Cu{Ph2P(C5H4FeC5H4)PPh2}LI] (5), [Cu2(PPh3)2LII] (6), [Cu2(Ph2PCH2PPh2)LII] (7), [Cu2{Ph2P(CH2)2PPh2}2LII] (8), [Cu2{Ph2P(CH2)3PPh2}2LII] (9), [Cu2{Ph2P(C5H4FeC5H4)PPh2}2LII] (10), [Cu8(Ph2PCH2PPh2)8LIIII4] (11), [Cu4{Ph2P(CH2)2PPh2}4LIII] (12), [Cu4{Ph2P(CH2)3PPh2}4LIII] (13) or [Cu4{Ph2P(C5H4FeC5H4)PPh2}4LIII] (14) complexes. The structures of these compounds were investigated by IR, 1H, 31P{1H} NMR spectroscopy; their compositions were examined by microanalysis. The luminescent properties of the complexes 1-14 in the solid state are reported.  相似文献   

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