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1.
Single crystals of [H3dien]·(FeF6)·H2O (I) and [H3dien]·(CrF6)·H2O (II) are obtained by solvothermal synthesis under microwave heating. I is orthorhombic (Pna21) with a=11.530(2) Å, b=6.6446(8) Å, c=13.787(3) Å, V=1056.3(2) Å3 and Z=4. II is monoclinic (P21/c) with a=13.706(1) Å, b=6.7606(6) Å, c=11.3181(9) Å, β=99.38(1)°, V=1034.7(1) Å3 and Z=4. The structure determinations, performed from single crystal X-ray diffraction data, lead to the R1/wR2 reliability factors 0.028/0.066 for I and 0.035/0.102 for II. The structures of I and II are built up from isolated FeF6 or CrF6 octahedra, water molecules and triprotonated amines. In both structures, each octahedron is connected by hydrogen bonds to six organic cations and two water molecules. The iron-based compound is also characterized by 57Fe Mössbauer spectrometry: the hyperfine structure confirms the presence of Fe3+ in octahedral coordination and reveals the existence of paramagnetic spin fluctuations.  相似文献   

2.
Two novel vanadium selenites {[VO(OH)(H2O)](SeO3)}4·2H2O 1 and (H3NCH2CH2NH3)[(VO)(SeO3)2] 2 were synthesized by hydrothermal method and their crystal structures were determined by single-crystal X-ray diffraction. It is characterized by inductively coupled plasma (ICP), thermogravimetric (TG) and elemental analyses. Compound 1 crystallizes in the monoclinic system, space group C2/c, a=21.2250(11) Å, b=12.6309(6) Å, c=17.0249(10) Å, β=96.830(3)°, V=4531.8(4) Å3 and Z=8, R1 [I>2σ(I)]=0.0344, wR2 [I>2σ(I)]=0.119; Compound 2 crystallizes in the monoclinic system, space group P21/c, a=9.6389(4) Å, b=6.9922(3) Å, c=15.0324(5) Å, β=102.297(2)°, V=989.90(7) Å3 and Z=4, R1 [I>2σ(I)]=0.0452, wR2 [I>2σ(I)]=0.117. {[VO(OH)(H2O)](SeO3)}4·2H2O has a 1D structure constructed from the {[VO(OH)(H2O)](SeO3)} chains. (H3NCH2CH2NH3)[(VO)(SeO3)2] has a layered structure composed of alternating VO5 and SeO3 units with protonated ethylenediamine as interlayer guest.  相似文献   

3.
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   

4.
The lanthanide sulphate octahydrates Ln2(SO4)3·8H2O (Ln=Ho, Tm) and the respective tetrahydrate Pr2(SO4)3·4H2O were obtained by evaporation of aqueous reaction mixtures of trivalent rare earth oxides and sulphuric acid at 300 K. Ln2(SO4)3·8H2O (Ln=Ho, Tm) crystallise in space group C2/c (Z=4, aHo=13.4421(4) Å, bHo=6.6745(2) Å, cHo=18.1642(5) Å, βHo=102.006(1) Å3 and aTm=13.4118(14) Å, bTm=6.6402(6) Å, cTm=18.1040(16) Å, βTm=101.980(8) Å3), Pr2(SO4)3·4H2O adopts space group P21/n (a=13.051(3) Å, b=7.2047(14) Å, c=13.316(3) Å, β=92.55(3) Å3). The vibrational and optical spectra of Ho2(SO4)3·8H2O and Pr2(SO4)3·4H2O are also reported.  相似文献   

5.
Two new vanadium squarates have been synthesized, characterized by infrared and thermal behavior and their structures determined by single crystal X-ray diffraction. Both structures are made of discrete, binuclear vanadium entity but in 1, [V(OH)(H2O)2(C4O4)]2·2H2O the vanadium atom is trivalent and the entity is neutral while in 2, (NH4)[(VO)2(OH)(C4O4)2(H2O)3]·3H2O, the vanadium atom is tetravalent and the entity is negatively charged, balanced by the presence of one ammonium ion. Both molecular anions are bridged by two terminal μ2 squarate ligands. 1 crystallizes in the triclinic system, space group P-1, with lattice constants a=7.5112(10) Å, b=7.5603(8) Å, c=8.2185(8) Å, α=106.904(8)°, β=94.510(10)°, γ=113.984(9)° while 2 crystallizes in the monoclinic system, space group C2/c, with a=14.9340(15) Å, b=6.4900(9) Å, c=17.9590(19) Å and β=97.927(12)°. From the magnetic point of view, V(III) binuclear species show ferromagnetic interactions at low temperatures. However, no anomalies pointing to magnetic ordering are observed down to 2 K.  相似文献   

6.
The X-ray crystal structures of a series of new compounds (H3O)2[{Mn(H2O)1.5}3{Re6Se8(CN)6}2]·19H2O (1), (Me4N)2[{Co(H2O)1.5}3{Re6S8(CN)6}2]·13H2O (2), (Me4N)2[{Co(H2O)1.5}3{Re6Se8(CN)6}2]·3H2O (3), (Et4N)2[{Mn(H2O)2}3{Re6Se8(CN)6}2]·6.5H2O (4), (Et4N)2[{Ni(H2O)2}3{Re6S8(CN)6}2]·6.5H2O (5), and (Et4N)2[{Co(H2O)2}3{Re6S8(CN)6}2]·10H2O (6) are reported. All six compounds are isostructural crystallizing in cubic space group with four formulae per unit cell. For compounds 1, 3-5 the following parameters were found: (1) a=19.857(2) Å, R1=0.0283; (3 at 150 K) a=19.634(1) Å, R1=0.0572; (4) a=20.060(2) Å, R1=0.0288; (5) a=19.697(2) Å, R1=0.0224. The structures consist three-dimensional cyano-bridged framework formed by cyano cluster anions [Re6Q8(CN)6]4−, Q=S, Se and transition metal cations, M2+=Mn2+, Co2+, Ni2+. Water molecules and large organic cations Me4N+ and Et4N+ are included in cavities of this framework. Porosity of the framework, its ability to accommodate different cations and water molecules by little changes in the structure, as well as distortion of coordination framework under loss of water of crystallization is discussed.  相似文献   

7.
The rare-earth dicarboxylate hybrid materials [Ce(H2O)]2[O2C(CH2)2CO2]3 ([Ce(Suc)]) and [Sm(H2O)]2[O2C(CH2)2CO2]3·H2O ([Sm(Suc)]) have been hydrothermally synthesized (200°C, 3 days) under autogenus pressure. [Ce(Suc)] is triclinic, a=7.961 (3) Å, b=8.176 (5) Å, c=14.32 (2) Å, α=97.07° (7), β=96.75° (8), γ=103.73° (6), and z=2. The crystal structure of this compound has been determined using 3120 unique single crystal data. The final refinements let the agreement factors R1 and wR2(F2) converge to 0.0138 and 0.0363, respectively. [Ce(Suc)] is built up from infinite chains of edge-sharing nine-fold coordinated cerium atoms running along [100]. These chains are interconnected by the carbon atoms of the succinate anions, leading to a three-dimensional hybrid framework. The cell constants of [Sm(Suc)], isotypic with monoclinic C2/c [Pr(H2O)]2[O2C(CH2)2CO2]3·H2O ([Pr(Suc)]), were refined starting from X-ray powder data: a=20.275 (3) Å, b=7.919 (6) Å, c=14.130 (3) Å, and β=121.45° (1). Despite its lower symmetry, [Ce(Suc)] presents an important structural filiation with [Sm(Suc)]  相似文献   

8.
The compounds M[PO2(OH)2]2·2H2O (M=Mg, Mn, Fe, Co, Ni, Zn, Cd) were prepared from super-saturated aqueous solutions at room temperature. Single-crystal X-ray structure investigations of members with M=Ni, Zn, Cd were performed at 295 and 120 K. The space-group symmetry is P21/n, Z=2. The unit-cell parameters are at 295/120 K for M=Ni: a=7.240(2)/7.202(2), b=9.794(2)/9.799(2), c=5.313(1)/5.285(1) Å, β=94.81(1)/94.38(1)°, V=375.4/371.9 Å3; M=Zn: a=7.263(2)/7.221(2), b=9.893(2)/9.899(3), c=5.328(1)/5.296(2) Å, β=94.79(1)/94.31(2)°, V=381.5/377.5 Å3; M=Cd: a=7.356(2)/7.319(2), b=10.416(2)/10.423(3), c=5.407(1)/5.371(2) Å, β=93.85(1)/93.30(2)°, V=413.4/409.1 Å3. Layers of corner-shared MO6 octahedra and phosphate tetrahedra are linked by three of the four crystallographically different hydrogen bonds. The fourth hydrogen bond (located within the layer) is worth mentioning because of the short Oh?O bond distance of 2.57-2.61 Å at room temperature (2.56-2.57 Å at 120 K); only for M=Mg it is increased to 2.65 Å. Any marked temperature-dependent variation of the unit-cell dimension is observed only vertical to the layers. The analysis of the infrared (IR) spectroscopy data evidences that the internal PO4 vibrations are insensitive to the size and the electronic configuration of the M2+ ions. The slight strengthening of the intra-molecular P-O bonds in the Mg salt is caused by the more ionic character of the Mg-O bonds. All IR spectra exhibit the characteristic “ABC trio” for acidic salts: 2900-3180 cm−1 (A band), 2000-2450 cm−1 (B band) and 1550-1750 cm−1 (C band). Both the frequency and the intensity of the A band provide an evidence that the PO2(OH)2 groups in M[PO2(OH)2]2·2H2O compounds form weaker hydrogen bonds as compared with other acidic salts with comparable O?O bond distances of about 2.60 Å. The observed shift of the O-H stretching vibrations of the water molecule in the order M=Mg>Mn≈Fe≈Co>Ni>Zn≈Cd has been discussed with respect to the influence of both the character and the strength of M↔H2O interactions.  相似文献   

9.
Two new layered gallophosphates Co(en)3·Ga3P4O16·5H2O (1) and trans-Co(dien)2·Ga3P4O16·3H2O (2) have been hydrothermally synthesized using the racemic mixture of chiral metal complex Co(en)3Cl3 and Co(dien)2Cl3 as the structure-directing agent, respectively. Their structures are determined by single-crystal X-ray diffraction analysis and further characterized by X-ray power diffraction, ICP, elemental, and TG analyses. The structures of 1 and 2 consist of vertex-linking GaO4 and PO3(=O) tetrahedral units forming macroanionic [Ga3P4O16]3− sheets with a 4.6-net. The 4.6-net is characteristic of chiral [3.3.3] propellane-like structural motifs. The sheets of 1 stack in an ABAB sequence, with a pair of enantiomers of chiral Co(en)33+ cations residing in the interlayer region. The sheets of 2 array in a helical fashion with an ABCDEF stacking sequence, with only one enantiomer of chiral Co(dien)23+ cations residing in the interlayer region. Structural elucidation of 1 and 2 reveals that there exist stereo-specific correspondence between the metal complex template and the structure of the inorganic host. Crystal data: 1, Co(en)3·Ga3P4O16·5H2O, orthorhombic, Pnna (No. 52), a=8.6618(2) Å, b=21.6071(5) Å, c=13.7426(4) Å, Z=4, R1=0.0337 (I>2σ(I)), wR2=0.0985 (all data); 2, Co(dien)2·Ga3P4O16·3H2O, hexagonal, P6522 (No. 179), a=8.5152(7) Å, b=8.5152(7) Å, c=63.278(8) Å, R1=0.1183 (I>2σ(I)), wR2=0.2864 (all data) and Z=6.  相似文献   

10.
Tren amine cations [(C2H4NH3)3N]3+ and zirconate or tantalate anions adopt a ternary symmetry in two hydrates, [H3tren]2·(ZrF7)2·9H2O and [H3tren]6·(ZrF7)2·(TaOF6)4·3H2O, which crystallise in R32 space group with aH = 8.871 (2) Å, cH = 38.16 (1) Å and aH = 8.758 (2) Å, cH = 30.112 (9) Å, respectively. Similar [H3tren]2·(MX7)2·H2O (M = Zr, Ta; X = F, O) sheets are found in both structures; they are separated by a water layer (Ow(2)-Ow(3)) in [H3tren]2·(ZrF7)2·9H2O. Dehydration of [H3tren]2·(ZrF7)2·9H2O starts at room temperature and ends at 90 °C to give [H3tren]2·(ZrF7)2·H2O. [H3tren]2·(ZrF7)2·H2O layers remain probably unchanged during this dehydration and the existence of one intermediate [H3tren]2·(ZrF7)2·3H2O hydrate is assumed. Ow(1) molecules are tightly hydrogen bonded with -NH3+ groups and decomposition of [H3tren]2·(ZrF7)2·H2O occurs from 210 °C to 500 °C to give successively [H3tren]2·(ZrF6)·(Zr2F12) (285 °C), an intermediate unknown phase (320 °C) and ZrF4.  相似文献   

11.
The crystal structure of the double salt CoCl2·MgCl2·8H2O has been determined by the X-ray diffraction method. It crystallizes in the space group with a=6.0976(9), b=6.308(1), c=8.579(3) Å, α=81.99(2)°, β=88.40°, γ=84.61(1)°, Z=1, and R=0.027. The crystal consists of two kinds of well separated octahedra, [CoCl4(H2O)2]2− and [Mg(H2O)6]2+. The former is unique as aquachloro complexes of Co2+. In order to elucidate the reason prepared as such unique complexes in the double salts, formation energies for [MCl4(H2O)2]2− and [M(H2O)6]2+ (M=Co, Mg) have been calculated by using the density functional methods, and it has been revealed that the formation energies of the first coordination sphere for the metal ions and the Cl?H2O hydrogen bond networks around [CoCl4(H2O)2]2− play a decisive role in forming [CoCl4(H2O)2]2− with the regular octahedral geometry in the double salt.  相似文献   

12.
The uranyl and neptunyl(VI) iodates, K3[(UO2)2(IO3)6](IO3)·H2O (1) and K[NpO2(IO3)3]·1.5H2O (2), have been prepared and crystallized under mild hydrothermal conditions. The structures of 1 and 2 both contain one-dimensional 1[AnO2(IO3)3]1−(An=U,Np) ribbons that consist of approximately linear actinyl(VI) cations bound by iodate anions to yield AnO7 pentagonal bipyramids. The AnO7 units are linked by bridging iodate anions to yield chains that are in turn coupled by additional iodate anions to yield ribbons. The edges of the ribbons are terminated by monodentate iodate anions. For 1 and 2, K+ cations and water molecules separate the ribbons from one another. In addition, isolated iodate anions are also found between 1[UO2(IO3)3]1− ribbons in 1. In order to aid in the assignment of oxidation states in neptunyl containing compounds, a bond-valence sum parameter of 2.018 Å for Np(VI) bound exclusively to oxygen has been developed with b=0.37 Å. Crystallographic data (193 K, MoKα, λ=0.71073): 1, triclinic, , a=7.0609(4) Å, b=14.5686(8)  Å, c=14.7047(8)  Å, α=119.547(1)°, β=95.256(1)°, γ=93.206(1)°, Z=2, R(F)=2.49% for 353 parameters with 6414 reflections with I>2σ(I); (203 K, MoKα, λ=0.71073): 2, monoclinic, P21/c, a=7.796(4)  Å, b=7.151(3)  Å, c=21.79(1)  Å, β=97.399(7)°, Z=4, R(F)=6.33% for 183 parameters with 2451 reflections with I>2σ(I).  相似文献   

13.
Hydrothermal reactions of VOSO4·3H2O, CdAc2·2H2O, NiCl2·6H2O, H3PO4, and H2O yield the first example of trimetallic phosphate materials, [Ni(H2O)4]Cd(VO)(PO4)21. The single-crystal X-ray diffraction shows that its structure consists of Cd/V/O binary metal oxide lamellas decorated by PO4 tetrahedra, which are further pillared by NiO2(H2O)4 octahedra to generate a neutral 3-D framework containing two intercrossing 8-MR channels where the coordinated water molecules protrude into. Thermal and magnetic behaviors of this material were also measured. Crystal data: CdNiVP2O13H8, orthorhombic Ibca (No.73), a=7.1307(2) Å, b=18.6248(3) Å, c=14.8046(2) Å, V=1966.17(7) Å3, Z=8.  相似文献   

14.
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   

15.
This paper describes the hydrothermal syntheses of two isostructural metal bisphosphonates: M2(O3PC6H4PO3)(H2O)2 [M=CoII (1), NiII (2)]. Single-crystal structure determination of compound 1 revealed a pillared layered structure in which the phenyl groups connect the inorganic layers of cobalt phosphonate. Crystal data for 1: orthorhombic, space group Pnnm, a=19.306(5), b=4.8293(12), c=5.6390(14) Å, V=525.7(2) Å3, Z=2. Magnetic susceptibility data indicate that antiferromagnetic interactions are mediated in both cases.  相似文献   

16.
Two isotypic layered rare-earth borate phosphates, K3Ln[OB(OH)2]2[HOPO3]2 (Ln=Yb, Lu), were synthesized hydrothermally and the crystal structures were determined by single-crystal X-ray diffraction (R3?, Z=3, Yb: a=5.6809(2) Å, c=36.594(5) Å, V=1022.8(2) Å3, Lu: a=5.6668(2) Å, c=36.692(2) Å, V=1020.4(1) Å3). The crystal structure can be described in terms of stacking of Glaserite-type slabs consisting of LnO6 octahedra interlinked by phosphate tetrahedra and additional layers of [OB(OH)2]- separated by K+ ions. Field and temperature dependent measurements of the magnetic susceptibility of the Yb-compound revealed Curie-Weiss paramagnetic behavior above 120 K (μeff=4.7 μB). Magnetic ordering was not observed down to 1.8 K.  相似文献   

17.
A new one-dimensional molybdenum oxide compound with manganese-o-phen subunit: [Mn(o-phen)(H2O)MoO4]·H2O (1) (o-phen=o-phenanthroline) was synthesized by thehydrothermal reaction of Na2MoO4·2H2O, MnSO4·H2O, oxalic acid, o-phenanthroline (o-phen) and water. Its structure was determined by elemental analyses, ESR spectrum, TG analysis, IR spectrum and single-crystal X-ray diffraction. Compound 1 crystallizes in triclinic system, space group P-1 with a=7.0401(2) Å, b=10.4498(2) Å, c=10.5720(2) Å, α=73.26(7)°, β=83.34(8)°, γ=77.33(9)°, V=725.5089(0) Å3, Z=2, and R1=0.0322 for 2337 observed reflections. Compound 1 exhibits one-dimensional chain structure. The chains are linked up via hydrogen bonding to 2D layers, which are further assembled through π-π stacking interactions to a 3D supermolecular structure.  相似文献   

18.
A new layered indium phosphate [Co(en)3][In3(H2PO4)6(HPO4)3]·H2O (1) has been synthesized solvothermally by using a racemic mix of chiral metal complex Co(en)3Cl3 as a template. Its structure is determined by single-crystal X-ray diffraction analysis and further characterized by X-ray powder diffraction, ICP, NMR and TG analyses. The inorganic layer is built up by alternation of In-centred octahedra (InO6) and P-centered tetrahedra (PO3(OH), PO2(OH)2, PO2(=O)(OH) and PO(=O)(OH)2) forming a 4.12-net. The metal complex cations locate in the interlayer region and interact with the host network through H-bonds. It is the first indium phosphate compound templated by a transition-metal complex and is isostructural with GaPO-CJ14. Crystal data: 1, monoclinic, space group P21/m (No. 11), a=9.1700(18) Å, b=22.6923(5) Å, c=9.9116(2) Å, β=107.87(3)°, Z=4, R1[I>2σ(I)]=0.0287 and wR2(all data)=0.0939.  相似文献   

19.
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   

20.
A new hydrated borate compound, [NH3CH2CHCH3NH3]][B8O11(OH)4]·H2O 1, has been synthesized in the presence of 1,2-diaminopropane acting as a structure-directing agent under mild conditions. Its structure was determined by single crystal X-ray diffraction and further characterized FTIR, elemental analysis, powder X-ray diffraction and thermogravimetric analysis. Compound 1 crystallizes in the monoclinic system, space group P21/c (No. 14), a=10.0787(7) Å, b=8.8482(6) Å, c=19.3097(4) Å, β=91.352(6)°, V=1721.53(2) Å3, and Z=4. The structure consists of infinite open-branched borate chains constructed from [B3O6(OH)] units, onto which the [B5O7(OH)3] groups are grafted. It represents the first example of one-dimensional borate templated by an organic amine. The adjacent borate chains are further linked together by extensive hydrogen bonds to form a 3D supramolecular network. The diprotonated organic amines and guest water molecules are filled in the free space of the hydrogen-bonded network and interact with the inorganic framework by extensive hydrogen bonds.  相似文献   

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