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1.
Rare‐Earth‐Metal Coordination Polymers: Synthesis and Crystal Structures of Five New Adipinates, [M2(Adi)3(H2O)4](AdiH2)(H2O)4 (M = La, Nd), [Er(Adi)(H2O)5]Cl(H2O) and [M(Adi)(H2O)5](NO3)(H2O) (M = Gd, Er) The new rare‐earth compounds [M2(Adi)3(H2O)4](AdiH2)(H2O)4 (M = La ( 1 ), Nd ( 2 )), [Er(Adi)(H2O)5]Cl(H2O) ( 3 ) and [M(Adi)(H2O)5](NO3)(H2O) (M = Gd ( 4 ), Er ( 5 )) were obtained from the reaction of adipinic acid with La(OH)3·xH2O, Nd2O3, ErCl3·6H2O, Gd(NO)3·xH2O and Er2O3, respectively. Their crystal structures were determined by single‐crystal X‐ray diffraction. The coordination polymers [M2(Adi)3(H2O)4](AdiH2)(H2O)4 crystallize in the triclinic space group (no. 2) with a = 875.4(1), b = 1000.4(2), c = 1179.0(2) pm, α = 74.70(1), β = 69.85(1), γ = 86.18(2)° and Z = 1 (crystal data for M = La, ( 1 )). The quasi‐isostructural compounds [Er(Adi)(H2O)5]Cl(H2O) ( 3 ) and [M(Adi)(H2O)5](NO3)(H2O) (M = Gd ( 4 ), Er ( 5 )) crystallize with monoclinic symmetry, space group C2/c (no. 15) with lattice parameters of a = 1231.5(1), b = 1532.6(1), c = 895.4(1) pm, β = 123.44(1)° and Z = 4 (crystal data for ( 3 )). The rare‐earth cations have the coordination numbers 10 ( 1 , 2 ) and 9 ( 3 , 4 and 5 ), respectively. The compounds [M2(Adi)3(H2O)4](AdiH2)(H2O)4 are constructed of infinite chains of edge‐sharig [MO8(H2O)2] polyhedra that are cross‐linked by adipinic acid molecules to form framework structures. In [Er(Adi)(H2O)5]Cl(H2O) ( 3 ) and [M(Adi)(H2O)5](NO3)(H2O) (M = Gd ( 4 ), Er ( 5 )) the central cations are bridged by adipinic acid molecules in a bidentate‐chelating manner to positively charged zigzag chains. Between these the counter ions and crystal water molecules are incorporated.  相似文献   

2.
Rare‐Earth‐Metal Coordination Polymers: Syntheses and Crystal Structures of Three New Glutarates, [Pr2(Glu)3(H2O)4] · 10.5H2O, [Pr(Glu)(H2O)2]Cl, and [Er(Glu)(GluH)(H2O)2] The new rare‐earth dicarboxylates [Pr2(Glu)3(H2O)4] · 10.5H2O ( 1 ), [Pr(Glu)(H2O)2]Cl ( 2 ) and [Er(Glu)(GluH)(H2O)2] ( 3 ) were obtained from the reactions of glutaric acid with PrCl3·6H2O and Er(OH)3, respectively. The crystal structures were determined by single‐crystal X‐ray diffraction. [Pr2(Glu)3(H2O)4] · 10,5H2O crystallizes in the orthorhombic space group Pnma (no. 62) with a = 871.7(4), b = 3105.0(9), c = 1308.3(9) pm and Z = 4. The crystals of [Pr(Glu)(H2O)2]Cl are monoclinic (I2/a; no. 15) with a = 786.2(1), b = 1527.6(2) c = 801.2(1) pm, β = 99.78(1)° and Z = 4. [Er(Glu)(GluH)(H2O)2] crystallizes in the monoclinic space group P21/a (no. 14) with lattice parameters of a = 882.4(1), b = 1375.3(2), c = 1267.4(2) pm, β = 107.13(1)° and Z = 4. The rare‐earth cations have the coordination numbers 10 ( 1 ), 8 + 1 ( 2 ) and 9 ( 3 ). The individual polyhedra are connected to chains and further to sheets in 1 and 2 and to double chains in 3 . Only in the water‐rich compound 1 there are channels that contain crystal water molecules. It, therefore, has a considerably lower density than 2 and 3 .  相似文献   

3.
The self‐assembly reaction of zinc ions with tetracyanometalates in the presence of the tridentate chelated ligand 2,2′:6′,2′′‐terpyridine (terpy) yielded three cyanide‐bridged bimetallic compounds of general formula Zn(terpy)(H2O)M(CN)4 [M = Ni ( 1 ), Pd ( 2 ), Pt ( 3 )]. Compounds 1 – 3 were characterized by X‐ray diffraction (XRD), infrared spectroscopy (IR), and thermogravimetric (TG) analysis. Single‐crystal XRD analysis revealed that compounds 1 – 3 are isostructural and the structure consists of [Zn(terpy)(H2O)]2+ moieties and [M(CN)4]2– units linked alternatively to generate a one‐dimensional (1D) linear chain. The chains are further connected together through hydrogen bonding and π–π stacking interactions, forming a 3D supramolecular network. IR spectroscopic analysis indicated the presence of cyanide groups and terpy ligands in the structure. TG and powder XRD results showed that compounds 1 – 3 have higher thermal stabilities and exhibited irreversible for desorption/resorption of one coordinated water molecule.  相似文献   

4.
The reaction of the nitrates M(NO3)3·6H2O (M = La, Pr) and (H3O)2PtCl6 led to yellow single crystals of [M(NO3)2(H2O)6]2[PtCl6]·2H2O (M = La, Pr) (monoclinic, P21/c, Z = 2, La/Pr: a = 697.4(3)/695.5(1), b = 1654.5(1)/1652.5(2), c = 1317.7(6)/1318.5(3) pm, β = 93.97°(7)/93.93°(2), Rall = 0.0169/0.0659) while the reaction of M(NO3)3·5H2O (M = Gd, Dy) and (H3O)2PtCl6 yielded yellow single crystals of [M(NO3)(H2O)7][PtCl6]·4H2O (monoclinic, P21/n, Z = 4, Gd/Dy: a = 838.72(3)/838.40(2), b = 2131.98(6)/2139.50(7), c = 1142.63(3)/1143.10(3) pm, β = 95.670(4)/95.698(3), Rall = 0.0475/0.0337). The crystal structures consist of octahedral [PtCl6]2? anions and complex [M(NO3)2(H2O)6]2+ and [M(NO3)(H2O)7]2+ cations, respectively. The thermal decomposition of both types of compounds leads via various steps to elemental platinum and the oxide chlorides MOCl (M = La, Pr, Gd, Dy).  相似文献   

5.
M(H2O)2(4,4′‐bipy)[C6H4(COO)2]·2H2O (M = Mn2+, Co2+) – Two Isotypic Coordination Polymers with Layered Structure Monoclinic single crystals of Mn(H2O)2(4,4′‐bipy)[C6H4(COO)2]·2H2O ( 1 ) and Co(H2O)2(4,4′‐bipy)[C6H4(COO)2]· 2H2O ( 2 ) have been prepared in aqueous solution at 80 °C. Space group P2/n (no. 13), Z = 2; 1 : a = 769.20(10), b = 1158.80(10), c = 1075.00(10) pm, β = 92.67(2)°, V = 0.9572(2) nm3; 2 : a = 761.18(9), b = 1135.69(9), c = 1080.89(9) pm, β = 92.276(7)°, V = 0.9337(2) nm3. M2+ (M = Mn, Co), which is situated on a twofold crystallographic axis, is coordinated in a moderately distorted octahedral fashion by two water molecules, two oxygen atoms of the phthalate anions and two nitrogen atoms of 4,4′‐biypyridine ( 1 : M–O 219.5(2), 220.1(2) pm, M–N 225.3(2), 227.2(2) pm; 2 : Co–O 212.7(2), 213.7(2) pm, Co–N 213.5(3), 214.9(3) pm). M2+ and [C6H4(COO)2)]2? build up chains, which are linked by 4,4′‐biyridine molecules to yield a two‐dimensional coordination polymer with layers parallel to (001).Thermogravimetric analysis in air of 1 indicated a loss of water of crystallization between 154 and 212 °C and in 2 between 169 and 222 °C.  相似文献   

6.
The title complexes [M(ImH)4(tfbdc)(H2O)] ( 1 : M=Co; 2 : M=Ni) (ImH=imidazole, tfbdc=2,3,5,6‐tetrafluoroterephthalate) were synthesized by the reaction of M(OAc)2·4H2O, H2tfbdc and ImH in water solution. The complexes were characterized by elemental analysis, IR spectra, thermogravimetric analysis, cyclic voltammetry and X‐ray single crystal structure analysis. Structural analysis reveals that 1 and 2 possess isostructure: monoclinic, P21/c, Z=4. M(II) ion in complexes 1 and 2 has a distorted octahedral geometry coordinated by one oxygen atom from water, one oxygen atom from tfbdc2? and four nitrogen atoms from ImHs. They are discrete zero‐dimensional molecular complexes. And the adjacent monomeric components are connected by hydrogen bonds to form a supramolecule. Electrochemical properties of the complexes 1 and 2 show that electron transfer of M(II) between M(III) in electrolysis is a quasi‐reversible process.  相似文献   

7.
Two new complexes [Zn2(phen)4(FCA)2](ClO4)2·(H2O)2 ( 1 ) and [Co2(phen)4 (FCA)2](ClO4)2·(H2O)2 (2) (FCA=anion of 3‐ferrocenyl‐2‐crotonic acid, phen=1,10‐phenanthroline) have been synthesized, and characterized by elemental analysis, IR, UV‐Vis spectra, thermal analyses, and single‐crystal X‐ray diffraction. Two M(II) (M=Zn or Co) ions are bridged by two FCA anions with syn‐anti bridging ligands, leading to dimeric cores, [M2(phen)4(FCA)2]2+, and each M(II) ion is six‐coordinated in a distorted octahedral geometry by two chelate phen ligands and two μ2‐carboxylate oxygen atoms from two FCA groups. The M(II)…M(II) intradimer distances are 0.4391 and 0.4462 nm in 1 and 2 , respectively. Electrochemical properties of the complexes have been discussed.  相似文献   

8.
The title saccharinate complexes, aqua[1,2‐benzisothiazol‐3(2H)‐onato 1,1‐dioxide‐N]bis(1,10‐phenanthroline‐N,N′)man­ganese(II) 1,2‐benz­isothia­zol‐3(2H)‐onate 1,1‐dioxide,[Mn(C7H4NO3S)(C12H8N2)2(H2O)](C7H4NO3S), and aqua[1,2‐benz­iso­thiazol‐3(2H)‐onato 1,1‐dioxide‐N]­bis­(2,2′‐bi­pyri­dine‐N,N′)­cobalt(II) 1,2‐benz­iso­thia­zol‐3(2H)‐onate 1,1‐di­oxide, [Co­(C7H4NO3S)­(C10H8N2)2­(H2O)]­(C7H4NO3S), have been prepared and their crystal structures determined at 150 K. The structure of the manganese complex consists of repeated alternating [Mn(phen)2(sac)(H2O)]+ cations and non‐coordinated saccharinate anions. The water molecule, bound to manganese as part of a slightly distorted octahedral arrangement, is hydrogen bonded to an O atom of the SO2 group in the saccharinate counter‐ion. In contrast, the cobalt complex has one pseudo‐octahedral [Co(bipy)2(sac)(H2O)]+ cation, with the cobalt‐bound water molecule hydrogen bonded to the N atom of the accompanying free saccharinate anion.  相似文献   

9.
Reactions of a freshly prepared Zn(OH)2‐2x(CO3)x · yH2O precipitate, phenanthroline with azelaic and sebacic acid in CH3OH/H2O afforded [Zn(phen)(C9H15O4)2] ( 1 ) and [Zn2(phen)2(H2O)2(C10H16O4)2] · 3H2O ( 2 ), respectively. They were structurally characterized by X‐ray diffraction methods. Compound 1 consists of complex molecules [Zn(phen)(C9H15O4)2] in which the Zn atoms are tetrahedrally coordinated by two N atoms of one phen ligand and two O atoms of different monodentate hydrogen azelaato groups. Intermolecular C(alkyl)‐H···π interactions and the intermolecular C(aryl)‐H···O and O‐H···O hydrogen bonds are responsible for the supramolecular assembly of the [Zn(phen)(C9H15O4)2] complexes. Compound 2 is built up from crystal H2O molecules and the centrosymmetric binuclear [Zn2(phen)2(H2O)2(C10H16O4)2] complex, in which two [Zn(phen)(H2O)]2+ moieties are bridged by two sebacato ligands. Through the intermolecular C(alkyl)‐H···O hydrogen bonds and π‐π stacking interactions, the binuclear complex molecules are assembled into layers, between which the lattice H2O molecules are sandwiched. Crystal data: ( 1 ) C2/c (no. 15), a = 13.887(2), b = 9.790(2), c = 22.887(3)Å, β = 107.05(1)°, U = 2974.8(8)Å3, Z = 4; ( 2 ) P1¯ (no. 2), a = 8.414(1), b = 10.679(1), c = 14.076(2)Å, α = 106.52(1)°, β = 91.56(1)°, γ = 99.09(1)°, U = 1193.9(2)Å3, Z = 1.  相似文献   

10.
Coordination Polymeric 1, 2‐Dithiooxalato and 1, 2‐Dithiosquarato Complexes. Syntheses and Structures of [BaCr2(bipy)2(1, 2‐dtox)4(H2O)2], [Ni(cyclam)(1, 2‐dtsq)]·2DMF, [Ni(cyclam)Mn(1, 2‐dtsq)2(H2O)2]·2H22, and [H3O][H5O2][Cu(cyclam)]3[Cu2(1, 2‐dtsq)3]2 1, 2‐Dithioxalate and 1, 2‐dithiosquarate ions have a pair of soft and hard donor centers and thus are suited for the formation of coordination polymeric complexes containing soft and hard metal ions. The structures of four compounds with building blocks containing these ligands are reported: In [BaCr2(bipy)2(1, 2‐dtox)4(H2O)2] Barium ions and pairs of Cr(bipy)(1, 2‐dtox)2 complexes form linear chains by the bisbidentate coordination of the dithiooxalate ligands towards Ba2+ and Cr3+. In [Ni(cyclam)(1, 2‐dtsq)]·2DMF short NÖH···O hydrogen bonds link the NiS2N4‐octahedra with C2v‐symmetry to an infinite chain. In [Ni(cyclam)Mn(1, 2‐dtsq)2(H2O)2]·2H2O the 1, 2‐dithiosquarato ligand shows a rare example of S‐coordination towards manganese(II). The sulfur atoms of cis‐MnO2S4‐polyedra are weakly coordinated towards the axial sites of square‐planar NiN4‐centers, thus forming a zig‐zag‐chain of Mn···Ni···Mn···Ni polyhedra. [H3O][H5O2][Cu (cyclam)]3[Cu2(1, 2‐dtsq)3]2 contains square planar [CuII(cyclam)]2+ ions and dinuclear [CuI2(1, 2‐dtsq)3]4— ions. Here each copper atom is trigonally planar coordinated by S‐donor atoms of the ligands. The Cu…Cu distance is 2.861(4)Å.  相似文献   

11.
Two coordination polymers, [Co(phen)(oba)(H2O)2] ( 1 ) and [Cd3(phen)3(oba)2(Hoba)2(H2O)2] ( 2 ) (oba = 4, 4′‐oxybis(benzoate), phen = 1, 10‐phenanthroline) have been synthesized under hydrothermal conditions. Complex 1 crystallizes in monoclinic, P21/n, a = 7.543(6), b = 33.05(2), c = 9.902(5)Å, β = 103.69(2)°, V = 2398(3)Å3, Z = 4; 2 in monoclinic, P2/n, a = 15.11(1), b = 10.069(8), c = 28.02(2)Å, β = 101.83(1)°, V = 4174(5)Å3, Z = 2. X‐ray single‐crystal diffraction investigations shows that the complexes 1 and 2 consist of helical chains, which are further assembled into layers and networks via supramolecular interactions such as π—π stacking interactions and hydrogen bonds, respectively. The results indicate that the coordination environment is one of the most important factors for assembly of single‐stranded helical chains into double‐stranded helical chains via supramolecular interactions.  相似文献   

12.
Preparation and Crystal Structures of New Complex Clorides of Lanthanides containing 3, 5‐Dimethylpyridinium Cations: (3, 5‐Dimethylpyridinium)2[LnCl4(H2O)2]Cl (Ln = La, Pr) and (3, 5‐Dimethylpyridinium)3[TbCl6] Crystals of the complex chlorides (3, 5‐dimethylpyridinium)2[LaCl4(H2O)2]Cl ( 1 ), (3, 5‐dimethylpyridinium)2[PrCl4(H2O)2]Cl ( 2 ) and (3, 5‐dimethylpyridinium)3[TbCl6] ( 3 ) have been prepared by reaction of LnCl3 · x H2O (Ln = La, Pr, Tb; x = 6‐7) with 3, 5‐dimethylpyridiniumchloride in ethanol/butanol solution. The crystal structures have been determined from single crystal X‐ray diffraction data. The compounds 1 and 2 are isotypic with each other and crystallize in the triclinic space group P1¯ (Z = 2). The 3, 5‐dimethylpyridinium cations are linked by hydrogen bonds to the anionic part of the structure built up by isolated chloride ions and strings of edge coupled triangulated dodecahedra [LnCl4/2Cl2(H2O)2]. The organic units are arranged forming a “π‐stacking”. 3 cristallizes monoclinically in the space group P21/c (Z = 4). The structure contains octahedral building units [TbCl6]3—. These octahedra are interconnected by the organic cations via hydrogen bonds forming chains parallel to [0 0 1].  相似文献   

13.
Wang Y  Feng L  Li Y  Hu C  Wang E  Hu N  Jia H 《Inorganic chemistry》2002,41(24):6351-6357
Two novel compounds, [Co(4,4'-bipy)(H(2)O)(4)](4-abs)(2).H(2)O (1) and [Mn(4,4'-bipy)(H(2)O)(4)](4-abs)(2).2H(2)O (2) (4,4'-bipy = 4,4'-bipyridine; 4-abs = 4-aminobenzenesulfonate), have been synthesized in aqueous solution and characterized by single-crystal X-ray diffraction, elemental analyses, UV-vis and IR spectra, and TG analysis. X-ray structural analysis revealed that 1 and 2 both possess unusual hydrogen-bonded three-dimensional (3-D) networks encapsulating one-dimensional (1-D) covalently bonded infinite [M(4,4'-bipy)(H(2)O)(4)](2+) (M = Co, Mn) chains. The 4-abs anions in 1 form 1-D zigzag chains through hydrogen bonds. These chains are further extended through crystallization water molecules into 3-D hydrogen-bonded networks with 1-D channels, in which the [Co(4,4'-bipy)(H(2)O)(4)](2+) linear covalently bonded chains are located. Crystal data for 1: C(22)H(30)CoN(4)O(11)S(2), monoclinic P2(1), a = 11.380(2) A, b = 8.0274(16) A, c = 15.670(3) A, alpha = gamma = 90 degrees, beta = 92.82(3) degrees, Z = 2. Compound 2 contains interesting two-dimensional (2-D) honeycomb-like networks formed by 4-abs anions and lattice water molecules via hydrogen bonding, which are extended through other crystallization water molecules into three dimensions with 1-D hexagonal channels. The [Mn(4,4'-bipy)(H(2)O)(4)](2+) linear covalent chains exist in these channels. Crystal data for 2: C(22)H(32)MnN(4)O(12)S(2), monoclinic P2(1)/c, a = 15.0833(14) A, b = 8.2887(4) A, c = 23.2228(15) A, alpha = gamma = 90 degrees, beta = 95.186(3) degrees, Z = 4.  相似文献   

14.
Seven new transition metal complexes formulated as [M2(1,4-tpbd)(diimine)2(H2O)2]4+ [M = Zn, Co, Ni, Cd; 1,4-tpbd = N,N,N′,N′-tetrakis(2-pyridylmethyl)benzene-1,4-diamine; diimine is a N,N-donor heterocyclic base like 1,10-phenanthroline (phen), 2,2′-bipyridine (bpy), 4,5-diazafluoren-9-one (dafo)] have been synthesized and structurally characterized by X-ray crystallography: [Zn2(1,4-tpbd)(phen)2(H2O)2]4+ (1), [Zn2(1,4-tpbd)(bpy)2(H2O)2]4+ (2), [Co2(1,4-tpbd)(phen)2(H2O)2]4+ (3), [Ni2(1,4-tpbd)(phen)2(H2O)2]4+ (4), [Ni2(1,4-tpbd)(bpy)2(H2O)2]4+ (5), [Ni2(1,4-tpbd)(dafo)2(H2O)2]4+ (6) and [Cd2(1,4-tpbd)(phen)2(H2O)2]4+ (7). Single crystal diffraction reveals that the metals in the complexes are all in a distorted octahedral geometry. The interactions of the seven complexes with calf thymus DNA (CT-DNA) have been investigated by UV absorption, fluorescence, circular dichroism spectroscopy and viscosity measurements. The apparent binding constants (Kapp) are calculated to be 5.2?×?105 M?1 for 1, 1.05?×?105 M?1 for 2, 5.76?×?105 M?1 for 3, 4.57?×?105 M?1 for 4, 1.29?×?105 M?1 for 5, 1.7?×?105 M?1 for 6, 2.53?×?105 M?1 for 7, the binding propensity to the calf thymus DNA in the order: 3 (Co-phen) > 1 (Zn-phen) > 4 (Ni-phen) > 7 (Cd-phen) > 6 (Ni-dafo) > 5 (Ni-bpy) > 2 (Zn-bpy). Furthermore, these complexes display efficient oxidative cleavage of supercoiled DNA; the Zn(II)/H2O2 and Cd(II)/H2O2 systems efficiently cleave DNA attributed to the peroxide ion coordinated to the Zn(II) and Cd(II), which enhanced their nucleophilicity, this is rare.  相似文献   

15.
Eight isomorphous metal‐organic frameworks: [Ln2(TATAB)2(H2O)(DMA)6]·5H2O (Ln = Sm ( 1 ), Eu ( 2 ), Gd ( 3 ), Tb ( 4 ), Dy ( 5 ), Er ( 6 ), Tm ( 7 ), Yb ( 8 )); TATAB = 4,4′,4″‐s‐triazine‐1,3,5‐triyl‐p‐aminobenzoate, DMA = N,N‐dimethylacetamide), were synthesized by the self‐assembly of lanthanide ions, TATAB, DMA and H2O. Single‐crystal X‐ray crystallography reveals they are three dimensional frameworks with 2‐fold interpenetration. Solid‐state photoluminescence studies indicate ligand‐to‐metal energy transfer is more efficient for compounds 2 and 4 which exhibit intense characteristic lanthanide emissions at room temperature.  相似文献   

16.
Iso‐type [MII(pdc)(DPphen)(H2O]·H2O compounds (M = Co or Cu, pdc = 2,6‐pyridinedicarboxylato(2‐) ligand and DPphen = 4,7‐diphenyl‐1,10‐Phenanthroline) were synthesized and studied by X‐ray diffraction, thermal and spectral methods. The N,N′‐equatorial bidentate DPphen‐copper(II) chelation imposes a mer‐N(equatorial)+O2(apical) conformation to pdc in the coordination polyhedron (type 4+1+1). In the Co(II) derivative, the coordination is of type 1+2+2+1 because of a lesser Jahn‐Teller distortion. In the crystals, π,π‐interligand interactions between phen ligands connect the complex molecules in multi‐stacked chains. Aqua···O(carboxyl) H‐bonding interactions reinforce the stacked chains and build double chains in 1D supramolecular structures parallel to the a axis. Non coordinated water connect these structures by H‐bonds.  相似文献   

17.
Colourless single crystals of [Hg(OH)](NO3)(H2O) were obtained by slow evaporation of an aqueous solution of Hg(NO3)2 and Bi(NO3)3. The crystal structure (orthorhombic, Pbca, Z = 8, a = 943.2(2), b = 697.6(1), c = 1349.0(2) pm, R1(all) = 0.0780) contains [Hg(OH)] = …OH–Hg–OH–Hg… zig zag chains (O–Hg–O angle: 168°, Hg–O–Hg angle: 112°, Hg–OH distance: 212 pm) to which one water molecule is attached loosely. The [Hg(OH)](H2O) chains are connected via bis‐monodentate‐bridging nitrate ions to corrugated layers that are stacked in the [001] direction. Hg2+ has an effective 2+2+2(+1) coordination.  相似文献   

18.
Reaction of aqueous AgNO(3) with aqueous M(3)[Cr(ox)(3)] in >or=3:1 molar ratio causes the rapid growth of large, cherry-black, light-stable crystals which are not Ag(3)[Cr(ox)(3)], but [M(0.5)(H(2)O)(3)]@[Ag(2.5)Cr(ox)(3)] (ox(2)(-) = oxalate, C(2)O(4)(2)(-); M = Na, K, Cs, Ag, or mixtures of Ag and a group 1 element). The structure of these crystals contains an invariant channeled framework, with composition [[Ag(2.5)Cr(ox)(3)](-)(0.5)]( infinity ), constructed with [Cr(ox)(3)] coordination units linked by Ag atoms through centrosymmetric [Cr-O(2)C(2)O(2)-Ag](2) double bridges. The framework composition [Ag(2.5)Cr(ox)(3)](-)(0.5) occurs because one Ag is located on a 2-fold axis. Within the channels there is a well-defined and ordered set of six water molecules, strongly hydrogen bonded to each other and some of the oxalate O atoms. This invariant channel plus water structure accommodates group 1 cations, and/or Ag cations, in different locations and in variable proportions, but always coordinated by channel water and some oxalate O atoms. The general formulation of these crystals is therefore [M(x)Ag(0.5-x)(H(2)O)(3)]@[Ag(2.5)Cr(ox)(3)]. Five different crystals with this structure are reported, with compositions 1 Ag(0.5)[Ag(2.5)Cr(ox)(3)](H(2)O)(3), 2 Cs(0.19)Ag(0.31)[Ag(2.5)Cr(ox)(3)](H(2)O)(3), 3 K(0.28)Ag(0.22)[Ag(2.5)Cr(ox)(3)](H(2)O)(3), 4 Cs(0.41)Ag(0.09)[Ag(2.5)Cr(ox)(3)](H(2)O)(3), and 5 Cs(0.43)Ag(0.07) [Ag(2.5)Cr(ox)(3)](H(2)O)(3). All crystallize in space group C2/c, with a approximately 18.4, b approximately 14.6, c approximately 12.3 A, beta approximately 113 degrees. Pure Ag(3)[Cr(ox)(3)](H(2)O)(3), which has the same crystal structure (1), was obtained from water by treating Li(3)[Cr(ox)(3)] with excess AgNO(3). Complete dehydration of all of these compounds occurs between 30 and 100 degrees C, with loss of diffraction, but rehydration by exposure to H(2)O(g) at ambient temperature leads to recovery of the original diffraction pattern. In single crystals, this reversible dehydration-hydration occurs without visually evident crystal change, but with loss of mechanical strength. We postulate a general mechanism for transport of water molecules along the channels, associated with local partial collapses of the channel framework, with concomitant bending but little breaking of the host Ag-O and Cr-O bonds, which is readily reversed.  相似文献   

19.
Reactions of H3tda (H3tda = 1H‐1, 2, 3‐triazole‐4, 5‐dicarboxylic acid) with Sm(NO3)3 · 6H2O, Eu(NO3)3 · 6H2O, and Tb(NO3)3 · 6H2O, in the presence of NaOH under hydrothermal conditions, produced three new coordination polymers, [Ln2(tda)2(H2O)3] · 5H2O [Ln = Sm ( 1 ), Eu ( 2 ), Tb ( 3 )]. These compounds were structurally characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis (TGA), PXRD and single‐crystal X‐ray diffraction. The single‐crystal X‐ray diffraction studies of compounds 1 – 3 reveal that all compounds are three‐dimensional porous structures with chiral frameworks. Furthermore, the luminescence studies of compound 2 and 3 in the solid state reveal that they are potential luminescent materials at room temperature.  相似文献   

20.
The complexes cis‐[SnCl4(H2O)2]·2H2O ( 1 ), [Sn2Cl6(OH)2(H2O)2]·4H2O ( 3 ), and [HL][SnCl5(H2O)]·2.5H2O ( 4 ) were isolated from a CH2Cl2 solution of equimolar amounts of SnCl4 and the ligand L (L=3‐acetyl‐5‐benzyl‐1‐phenyl‐4, 5‐dihydro‐1, 2, 4‐triazine‐6‐one oxime, C18H18N4O2) in the presence of moisture. 1 crystallizes in the monoclinic space group Cc with a = 2402.5(1) pm, b = 672.80(4) pm, c = 1162.93(6) pm, β = 93.787(6)° and Z = 8. 4 was found to crystallize monoclinic in the space group P21, with lattice parameters a = 967.38(5) pm, b = 1101.03(6) pm, c = 1258.11(6) pm, β = 98.826(6)° and Z = 2. The cell data for the reinvestigated structures are: [SnCl4(H2O)2]·3H2O ( 2 ): a = 1227.0(2) pm, b = 994.8(1) pm, c = 864.0(1) pm, β = 103.86(1)°, with space group C2/c and Z = 4; 3 : a = 961.54(16) pm, b = 646.29(7) pm, c = 1248.25(20) pm, β = 92.75(1)°, space group P21/c and Z = 4.  相似文献   

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