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1.
The two new compounds, Sr4Cu3(AsO4)2(AsO3OH)4·3H2O (1) and Ba2Cu4(AsO4)2(AsO3OH)3(2), were synthesized under hydrothermal conditions. They represent previously unknown structure types and are the first compounds synthesized in the systems SrO/BaO-CuO-As2O5-H2O. Their crystal structures were determined by single-crystal X-ray diffraction [space group C2/c, a=18.536(4) Å, b=5.179(1) Å, c=24.898(5) Å, β=93.67(3)°, V=2344.0(8) Å3, Z=4 for 1; space group P42/n, a=7.775(1) Å, c=13.698(3) Å, V=828.1(2) Å3, Z=2 for 2]. The crystal structure of 1 is related to a group of compounds formed by Cu2+-(XO4)3− layers (X=P5+, As5+) linked by M cations (M=alkali, alkaline earth, Pb2+, or Ag+) and partly by hydrogen bonds. In 1, worth mentioning is the very short hydrogen bond length, D···A=2.477(3) Å. It is one of the examples of extremely short hydrogen bonds, where the donor and acceptor are crystallographically different. Compound 2 represents a layered structure consisting of Cu2O8 centrosymmetric dimers crosslinked by As1φ4 tetrahedra, where φ is O or OH, which are interconnected by Ba, As2 and hydrogen bonds to form a three-dimensional network. The layers are formed by Cu2O8 centrosymmetric dimers of CuO5 edge-sharing polyhedra, crosslinked by As1O4 tetrahedra. Vibrational spectra (FTIR and Raman) of both compounds are described. The spectroscopic manifestation of the very short hydrogen bond in 1, and ABC-like spectra in 2 were discussed.  相似文献   

2.
Phase transitions in the elpasolite-type K3AlF6 complex fluoride were investigated using differential scanning calorimetry, electron diffraction and X-ray powder diffraction. Three phase transitions were identified with critical temperatures , and . The α-K3AlF6 phase is stable below T1 and crystallizes in a monoclinic unit cell with a=18.8588(2)Å, b=34.0278(2)Å, c=18.9231(1)Å, β=90.453(1)° (a=2accc, b=4bc, c=ac+2cc; ac, bc, cc—the basic lattice vectors of the face-centered cubic elpasolite structure) and space group I2/a or Ia. The intermediate β phase exists only in very narrow temperature interval between T1 and T2. The γ polymorph is stable in the T2<T<T3 temperature range and has an orthorhombic unit cell with a=36.1229(6)Å, b=17.1114(3)Å, c=12.0502(3)Å (a=3ac−3cc, b=2bc, c=ac+cc) at 250 °C and space group Fddd. Above T3 the cubic δ polymorph forms with ac=8.5786(4)Å at 400 °C and space group . The similarity between the K3AlF6 and K3MoO3F3 compounds is discussed.  相似文献   

3.
This paper reports the syntheses and characterization of two phosphonate compounds Cd{(2-C5H4NO)CH(OH)PO3}(H2O)2 (1) and Zn{(4-C5H4NO)CH(OH)PO3} (2) based on hydroxy(2-pyridyl N-oxide)methylphosphonic and hydroxy(4-pyridyl N-oxide)methylphosphonic acids. Compound 1 has a chain structure in which dimers of edge-shared {CdO6} octahedra are linked by {CPO3} tetrahedra through corner-sharing. The pyridyl rings reside on the two sides of the inorganic chain. Compound 2 has a layer structure where the inorganic chains made up of corner-sharing {ZnO4} and {CPO3} tetrahedra are covalently connected by pyridyl N-oxide groups. Crystal data for 1: triclinic, space group , a=6.834(1) Å, b=7.539(1) Å, c=10.595(2) Å, α=84.628(3)°, β=74.975(4)°, γ=69.953(4)°. For 2: triclinic, space group , a=5.219(1) Å, b=8.808(2) Å, c=9.270(2) Å, α=105.618(5)°, β=95.179(4)°, γ=94.699(4)°.  相似文献   

4.
5.
The solid-state reactions of UO3 and WO3 with M2CO3 (M=Na, K, Rb) at 650°C for 5 days result, accordingly the starting stoichiometry, in the formation of M2(UO2)(W2O8) (M=Na (1), K (2)), M2(UO2)2(WO5)O (M=K (3), Rb (4)), and Na10(UO2)8(W5O20)O8 (5). The crystal structures of compounds 2, 3, 4, and 5 have been determined by single-crystal X-ray diffraction using Mo(Kα) radiation and a charge-coupled device detector. The crystal structures were solved by direct methods and Fourier difference techniques, and refined by a least-squares method on the basis of F2 for all unique reflections. For (1), unit-cell parameters were determined from powder X-ray diffraction data. Crystallographic data: 1, monoclinic, a=12.736(4) Å, b=7.531(3) Å, c=8.493(3) Å, β=93.96(2)°, ρcal=6.62(2) g/cm3, ρmes=6.64(1) g/cm3, Z=4; 2, orthorhombic, space group Pmcn, a=7.5884(16) Å, b=8.6157(18) Å, c=13.946(3) Å, ρcal=6.15(2) g/cm3, ρmes=6.22(1) g/cm3, Z=8, R1=0.029 for 80 parameters with 1069 independent reflections; 3, monoclinic, space group P21/n, a=8.083(4) Å, b=28.724(5) Å, c=9.012(4) Å, β=102.14(1)°, ρcal=5.83(2) g/cm3, ρmes=5.90(2) g/cm3, Z=8, R1=0.037 for 171 parameters with 1471 reflections; 4, monoclinic, space group P21/n, a=8.234(1) Å, b=28.740(3) Å, c=9.378(1) Å, β=104.59(1)°, ρcal=6.13(2) g/cm3,  g/cm3, Z=8, R1=0.037 for 171 parameters with 1452 reflections; 5, monoclinic, space group C2/c, a=24.359(5) Å, b=23.506(5) Å, c=6.8068(14) Å, β=94.85(3)°, ρcal=6.42(2) g/cm3,  g/cm3, Z=8, R1=0.036 for 306 parameters with 5190 independent reflections. The crystal structure of 2 contains linear one-dimensional chains formed from edge-sharing UO7 pentagonal bipyramids connected by two octahedra wide (W2O8) ribbons formed from two edge-sharing WO6 octahedra connected together by corners. This arrangement leads to [UW2O10]2− corrugated layers parallel to (001). Owing to the unit-cell parameters, compound 1 probably contains similar sheets parallel to (100). Compounds 3 and 4 are isostructural and the structure consists of bi-dimensional networks built from the edge- and corner-sharing UO7 pentagonal bipyramids. This arrangement creates square sites occupied by W atoms, a fifth oxygen atom completes the coordination of W atoms to form WO5 distorted square pyramids. The interspaces between the resulting [U2WO10]2− layers parallel to plane are occupied by K or Rb atoms. The crystal structure of compound 5 is particularly original. It is based upon layers formed from UO7 pentagonal bipyramids and two edge-shared octahedra units, W2O10, by the sharing of edges and corners. Two successive layers stacked along the [100] direction are pillared by WO4 tetrahedra resulting in sheets of double layers. The sheets are separated by Na+ ions. The other Na+ ions occupy the rectangular tunnels created within the sheets. In fact complex anions W5O2010− are built by the sharing of the four corners of a WO4 tetrahedron with two W2O10 dimmers, so, the formula of compound 5 can be written Na10(UO2)8(W5O20)O8.  相似文献   

6.
Two uranyl tellurates, AgUO2(HTeO5) (1) and Pb2UO2(TeO6) (2), were synthesized under hydrothermal conditions and were structurally, chemically, and spectroscopically characterized. 1 crystallizes in space group Pbca, a=7.085(2) Å, b=11.986(3) Å, c=13.913(4) Å, V=1181.5(5) Å3, Z=8; 2 is in P2(1)/c, a=5.742(1) Å, b=7.789(2) Å, c=7.928(2) Å, V=90.703(2) Å3, and Z=2. These are the first structures reported for uranyl compounds containing tellurate. The U6+ cations are present as (UO2)2+ uranyl ions that are coordinated by O atoms to give pentagonal and square bipyramids in compounds 1 and 2, respectively. The structural unit in 1 is a sheet consisting of chains of edge-sharing uranyl pentagonal bipyramids that are one bipyramid wide, linked through the dimers of TeO6 octahedra. In 2, uranyl square bipyramids share each of their equatorial vertices with different TeO6 octahedra, giving a sheet with the autunite-type topology. Sheets in 1 and 2 are connected through the low-valence cations that are located in the interlayer region. The structures of 1 and 2 are compared to those of uranyl compounds containing octahedrally coordinated cations.  相似文献   

7.
The hydrosulfido complexes CpRu(L)(L′)SH react with one equivalent of O-alkyl oxalyl chlorides (ROCOCOCl) to form the corresponding O-alkylthiooxalate complexes CpRu(L)(L′)SCOCO2R (L = L′ = PPh3 (1), (2); L = PPh3, L′ = CO (3); R = Me (a), Et (b)). The reactions of the hydrosulfido complexes with half equivalent of oxalyl chloride produce the bimetallic complexes [CpRu(L)(L′)SCO]2 (L = L′ = PPh3 (4), (5); L = PPh3, L′ = CO (6)). The crystal structures of CpRu(PPh3)2SCOCO2Me (1a) and CpRu(dppe)SCOCO2Et (2b) are reported.  相似文献   

8.
Using biprotonated dabco (1,4-diazabicyclo[2.2.2]octane) or pipz (piperazine) as counter cations, mixed-ligand fluoromanganates(III) with dimeric anions could be prepared from hydrofluoric acid solutions. The crystal structures were determined by X-ray diffraction on single crystals: dabcoH2[Mn2F8(H2O)2]·2H2O (1), space group P21, Z = 2, a = 6.944(1), b = 14.689(3), c = 7.307(1) Å, β = 93.75(3)°, R1 = 0.0240; pipzH2[Mn2F8(H2O)2]·2H2O (2), space group , Z = 2, a = 6.977(1), b = 8.760(2), c = 12.584(3) Å, α = 83.79(3), β = 74.25(3), γ = 71.20(3)°, R1 = 0.0451; (dabcoH2)2[Mn2F8(H2PO4)2] (3), space group P21/n, Z = 4, a = 9.3447(4), b = 12.5208(4), c = 9.7591(6) Å, β = 94.392(8)°, R1 = 0.0280. All three compounds show dimeric anions formed by [MnF5O] octahedra (O from oxo ligands) sharing a common edge, with strongly asymmetric double fluorine bridges. In contrast to analogous dimeric anions of Al or Fe(III), the oxo ligands (H2O (1,2) or phosphate (3)) are in equatorial trans-positions within the bridging plane. The strong pseudo-Jahn-Teller effect of octahedral Mn(III) complexes is documented in a huge elongation of an octahedral axis, namely that including the long bridging Mn-F bond and the Mn-O bond. In spite of different charge of the anion in the fluoride phosphate, the octahedral geometry is almost the same as in the aqua-fluoro compounds. The strong distortion is reflected also in the ligand field spectra.  相似文献   

9.
10.
A comparative investigation of the coordination behaviour of the 17-membered, N3O2-donor macrocycle, 1,12,15-triaza-3,4:9,10-dibenzo-5,8-dioxacycloheptadecane, L, with the soft metal ions Ag(I), Cd(II), Hg(II), and Pd(II) is reported. The X-ray structures of 12 complexes have been determined and a range of structural types, including both mononuclear and dinuclear species, shown to occur. In particular cases the effect of anion variation on the resulting structures has been investigated; L reacts with AgX (X = NO3, ClO4, PF6, OTf and CN) to yield related 2:2 (metal:ligand) complexes of types [Ag2L2(NO3)2] (1), [Ag2L2](ClO4)2 · 2DMF (2), [Ag2L2](PF6)2 · 2DMF (3), [Ag2L2](OTf)2 (4) and [Ag2L2(μ-CN)][Ag(CN)2] · H2O (5). In all five complexes the ether oxygens of each ring are unbound. In 1–4 the macrocycles are present in sandwich-like arrangements that shield the dinuclear silver centres, with each silver bonded to two nitrogen donors from one L and one nitrogen from a second L. A Ag···Ag contact is present between each metal centre such that both centres can be described as showing distorted tetrahedral geometries. In the case of 5 a rare single μ2-κC:κC symmetrically bridging two-electron-donating cyano bridge links silver ions [Ag···Ag distance, 2.7437(10) Å]; the macrocyclic ligands are orientated away from the dinuclear metal centres. In contrast to the behaviour of silver, reaction of cadmium(II) perchlorate with L resulted in a mononuclear sandwich-like complex of type [CdL2](ClO4)2 · CH3CN (6). Again, the ether oxygens do not coordinate, with each L binding to the cadmium centre only via its three nitrogen donors in a facial arrangement such that a distorted octahedral coordination geometry is attained. Reaction of L with HgX2 (X = ClO4, SCN and I) yielded the monomeric species [HgL(ClO4)2] (7), [HgL(SCN)2]·CH3CN (8) and [Hg2L2](HgI4)2 · 2L (9), in which all five donors of L are bound to the respective mercury centres. However, reaction of L with Hg(NO3)2 in dichloromethane/methanol gave a mononuclear sandwich-like complex [HgL2](NO3)2 · 2CH3OH (10) without anion coordination. Reaction of K2PdCl4 and Pd(NO3)2 with L yielded the 1:1 complexes [PdLCl]Cl · H2O (11) and [PdL(NO3)]NO3 · CH3OH (12), respectively, in which the metal is bound to three nitrogen donors from L along with the corresponding chloride or nitrate anion. Each palladium adopts a distorted square-planar coordination geometry; once again the ether oxygens are not coordinated.  相似文献   

11.
To study the Ru-M interactions and their effects on 31P NMR, complexes [Ru(CO)3(Ph2Ppy)2] (py = pyridine) (1) and [Ru(CO)3(Ph2Ppy)2MCl2] (M = Zn, 2; Cd, 3; Hg, 4) were calculated by density functional theory (DFT) PBE0 method. Moreover, the PBE0-GIAO method was employed to calculate the 31P chemical shifts in complexes. The calculated 31P chemical shifts in 1-3 follow 2 > 3 > 1 which are consistent to experimental results, proving that PBE0-GIAO method adopted in this study is reasonable. This method is employed to predict the 31P chemical shift in designed complex 4. Compared with 1, the 31P chemical shifts in 2-4 vary resulting from adjacent Ru-M interactions. The Ru → M or Ru ← M charge-transfer interactions in 2-4 are revealed by second-order perturbation theory. The strength order of Ru → M interactions is the same as that of the P-Ru → M delocalization with Zn > Cd > Hg, which coincides with the order of 31P NMR chemical shifts. The interaction of Ru → M, corresponding to the delocalization from 4d orbital of Ru to s valence orbital of M2+, results in the delocalization of P-Ru → M, which decreases the electron density of P nucleus and causes the downfield 31P chemical shifts. Except 2, the back-donation effect of Ru ← M, arising from the delocalization from s valence orbital of M2+ to the valence orbital of Ru, is against the P-Ru → M delocalization and results in the upfield 31P chemical shifts in 4. Meanwhile, the binding energies indicate that complex 4 is stable and can be synthesized experimentally. However, as complex [Ru(CO)3(Ph2Ppy)2HgCl]+5 is more stable than 4, the reaction of 1 with HgCl2 only gave 5 experimentally.  相似文献   

12.
13.
A new three-dimensional non-interpenetrating coordination polymer, [{Cu(dps)2(SO4)}·3H2O·DMF]n (1) (dps=4,4′-dipyridyl sulfide) was synthesized and structurally characterized. 1 crystallizes in triclinic system, space group P−1 with cell parameters of a=10.9412(1) Å, b=11.8999(1) Å, c=12.5057(1) Å, V=1400.7(3) Å3, Z=2, Dc=1.573 g cm−3, F(0 0 0)=686, μ=1.059 mm−1. R1=0.0436, wR2=0.1148. In the polymeric architecture, serve as bridging coligands to connect highly puckered [Cu2(dps)2]n frameworks resulting in a 3D motif containing channels for guest molecule inclusion. Quantum chemistry calculation shows that the third-order NLO properties of polymer 1 are controlled by groups and dps ligands, and metal ions have less influence on the third-order NLO properties.  相似文献   

14.
Two new isotypic phosphates LiNi2H3(P2O7)2 (1) and LiCo2H3(P2O7)2 (2) have been hydrothermally synthesized and structurally characterized by the single-crystal X-ray diffraction technique. They crystallize in the monoclinic space group C2/c with the lattice: a=10.925(2) Å, b=12.774(3) Å, c=8.8833(18) Å, β=123.20(3)° for 1 and a=10.999(2) Å, b=12.863(3) Å, c=8.9419(18) Å, β=123.00(3)° for 2. The transition metal atoms are octahedrally coordinated, whereas the lithium and phosphorus atoms are all tetrahedrally coordinated. As the lithium-induced derivatives of MH2P2O7 (M=Ni, Co), 1 and 2 possess the same structure with MH2P2O7 in terms of topology, comprising the MO6 zigzag chains and P2O7 as the interchain groups. The magnetisms of 1 and 2 could be interpreted by adopting a quasi-one-dimensional (1D) zigzag chain model as that in their parent compounds: both 1 and 2 have ferromagnetic (FM) NiO6/CoO6 chains; 1 shows a FM cluster glass behavior at low temperatures, which is originated from the possible antiferromagnetic (AFM) next-nearest-neighbour intrachain interactions; 2 shows a AFM ordering at TN=2.6 K and a metamagnetic transition at HC=4.2 kOe at 1.8 K.  相似文献   

15.
16.
A novel three-dimensional (3D) transition metal selenite Fe3(H2O)(SeO3)3 (1) has been hydrothermally synthesized and characterized by the elemental analyses, IR spectrum, TG analysis and the single-crystal X-ray diffraction. Compound 1 crystallizes in the triclinic system, space group , with a=8.0916(16) Å, b=8.2089(16) Å, c=8.5679(17) Å, α=69.21(3)°, β=62.74(3)°, γ=67.16(3)°, Z=2, and R1[I>2σ(I)]=0.0379. Compound 1 exhibits an interesting 3D framework formed by {FeO6} octahedra and {SeO3} trigonal pyramids via the corner- and/or edge-sharing mode. Furthermore, compound 1 consists of left-handed and right-handed helical chains, which are further entangled to form the double helical chains.  相似文献   

17.
The P63 (a=2ap, b=2bp, c=cp) crystal structure reported for BaAl2O4 at room temperature has been carefully re-investigated by a combined transmission electron microscopy and neutron powder diffraction study. It is shown that the poor fit of this P63 (a=2ap, b=2bp, c=cp) structure model for BaAl2O4 to neutron powder diffraction data is primarily due to the failure to take into account coherent scattering between different domains related by enantiomorphic twinning of the P6322 parent sub-structure. Fast Fourier transformation of [0 0 1] lattice images from small localized real space regions (∼10 nm in diameter) are used to show that the P63 (a=2ap, b=2bp, c=cp) crystal structure reported for BaAl2O4 is not correct on the local scale. The correct local symmetry of the very small nano-domains is most likely orthorhombic or monoclinic.  相似文献   

18.
Two organic-inorganic hybrid compounds, Ga2(4,4′-bpy)(PO4)2, 1, and Ga2(4,4′-bpy)(AsO4)2, 2, have been synthesized under hydrothermal conditions and structurally characterized by single-crystal X-ray diffraction. The two compounds are isostructural and crystallize in the triclinic space group (No. 2) with a=4.9723(9) Å, b=5.770(1) Å, c=11.812(2) Å, α=78.268(3)°, β=89.159(3)° γ=88.344(3)°, V=331.7(2) Å3, Z=1, and R1=0.0377 for 1, and a=5.1111(7) Å, b=5.9327(8) Å, c=11.788(2) Å, α=79.497(2)°, β=88.870(2)°, γ=88.784(2)°, V=351.3(2) Å3, and R1=0.0264 for 2. The structure consists of neutral sheets of GaXO4 (X=P or As) which are pillared through 4,4′-bipyridine ligands. Each oxide layer, which is formed only by four-membered rings, is constructed from corner-sharing GaO4N trigonal bipyramids and XO4 tetrahedra. The title compounds are two of the few examples in which the gallium atoms are exclusively five-coordinate.  相似文献   

19.
A new 1,6-hexyldiamine heptaborate, [H3N(CH2)6NH3][B7O10(OH)3] (1), has been solvothermally synthesized and characterized by single-crystal X-ray diffraction, FTIR, elemental analysis, and thermogravimetric analysis. Compound 1 crystallizes in monoclinic system, space group P21/n with a=8.042(2) Å, b=20.004(4) Å, c=10.103(2) Å, and β=90.42(3)°. The anionic [B7O10(OH)3]n2n layers are interlinked via hydrogen bonding to form a 3D supramolecular network containing large channels, in which the templated [H3N(CH2)6NH3]2+ cations are located.  相似文献   

20.
A novel metal-organic framework (MOF) based on a tetranuclear copper cluster and a linear organic ligand formulated as [Cu4OCl6(DABCO)2]·0.5DABCO·4CH3OH (denoted as MFU-5, MFU=Metal-Organic Framework, Ulm University; DABCO=1,4-diazabicyclo[2.2.2]octane), was prepared via solvothermal synthesis. In contrast with common MOF synthesis strategies, MFU-5 is assembled from pre-defined molecular secondary building units, i.e. {Cu4OCl6} moieties, which become the nodes of the coordination framework. The title compound was characterized by single crystal X-ray diffraction, variable temperature powder diffraction (VT-XRPD), thermal analysis, as well as IR- and UV/Vis spectroscopy. Crystal data for MFU-5: hexagonal, P6/mcc (no. 192), a=25.645(9), c=17.105(11) Å, V=9742(8) Å3, Z=12, 1690 structure factors, R[F2>2σ(F2)]=0.049. MFU-5 is a 3D metal-organic framework with 1D channels running along the c-axis hosting DABCO and methanol solvent molecules. The framework displays a zeolite-like structure constructed from mso cages, which represents the composite building units in the zeolites SSF, MSO and SZR. Two-fold interpenetration is observed between these building units. TG/DTA-MS and VT-XRPD characterization reveal a stepwise release of methanol and DABCO molecules upon heating, eventually resulting in a structural change into a non-porous material.  相似文献   

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