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1.
The Crystal Structure of Na2NiAlF7 — a Contribution to the Problem of the True Space Group of Orthorhombic Weberites The X-ray single crystal structure determination of the orthorhombic weberite Na2NiAlF7 (a = 707.4(2), b = 1003.8(2), c = 731.5(1) pm; Z = 4) was performed in space group Imma, after all reflections hk0 with h(k) = 2n + 1 could be eliminated, as they proved simulated by Renninger effect and/or λ/2 reflections. The alternative space groups Imm2 resp. I212121 of former weberite structure determinations thus became obsolete. The refinement using 880 independent reflections ended at wR = 0.0232. The resulting average distances within the framework of octahedra are Ni? F = 197.3, Al? F = 180.4 pm.  相似文献   

2.
The Crystal Structures of the Weberites Na2CuScF7 and Na2ZnAlF7 At single crystals of the orthorhombic weberites Na2CuScF7 (Pmnb, Z = 4) and Na2ZnAlF7 (Imma, Z = 4) X-ray structure determinations were performed. Na2CuScF7 (Na2ZnAlF7): a = 726.0 (709.2), b = 1053.4 (1009.2), c = 765.8 (733.7) pm; R1 = 0.030 (0.042) for 887 (363) observed and independent reflections. The resulting average distances of the octahedrally coordinated metal atoms are: Cu? F = 200.7 pm, Sc? F = 201.7 pm; Zn? F = 198.8 pm, Al? F = 180.1 pm. Some structural relations and the variation in the bridge angles of the corner-sharing octahedra are discussed.  相似文献   

3.
The mixed valence compound Na2Fe2F7 crystallizes in the monoclinic weberite structure of the Na2CuFeF7-II type (M-II), space group C2/c, Z = 16, a = 12.676, b = 7.422, c = 24.710 Å, β = 99.97°. Refinement on F2 led to wR(F2) = 0.117 for all 2 645 reflections, R = 0.057 for 1 258 refl. with Fo > 4σ(F). On the basis of this and other recent single crystal investigations the structures of weberites Na2MIIMIIIF7 are classified in four main structure types: O-I is the ‘classical’ orthorhombic weberite type (S.G. Imma) encountered e.g. in the mineral Na2MgAlF7, from which two lower symmetric variants O-II (Na2CuCrF7 type) and O-III (Na2NiInF7) are deriving. The second M-I and third M-II basic type are monoclinic (e. g. Na2CuFeF7-I and -II), the fourth type T is trigonal (Na2MnFeF7). The structural relations within the weberite family are discussed and the connections established, which allow to regard these weberites as well as the pyrochlores as subtraction derivatives of the fluorite type.  相似文献   

4.
On Tantalates and Niobates ‘rich in Cations’. On Na5TaO5 and Na5NbO5 Colourless, transparent single crystals of Na5TaO5 [annealed mixtures of Na2O, Li2O, and Ta2O5, Na : Li : Ta = 6.6 : 1.1 : 1, Ni-cylinder, 1000°C, 75 d] as well as Na5NbO5 [annealed mixtures of Na2O, Li2O, and Nb2O5, Na : Li : Nb = 6.6 : 1.1 : 1, Ni-cylinder, 1000°C, 75 d] have been prepared. Single crystal data show that both isotypic oxides represent a deformed variant of the NaCl-type of structure [Na5TaO5: 1154 from 1250 I0 (hkl), four-cycle diffractometer Philips PW 1100, ω2-θ scan, Ag? Kα , R = 4.88%, space group c2/c with a = 629.3(1) pm, b = 1025.4(2) pm, c = 1004.6(2) pm, b? 106.80(2)°, z = 4 and Na5NbO5: 998 from 1247 I0(hkl), four-cycle diffractometer Philips PW 1100, ω-2θ scan, Ag? Kα , R = 8.58% and Rw = 7.67%, space group C2/2 with a = 629.1(1) pm, b = 1024.4(2) pm, c = 1004.2(2) pm, b? = 106.80(2)°, Z = 4]. The Madelung Part of Lattice Energy, MAPLE, and Effective Coordination Numbers, ECoN, the latter derived from Mean Effective Fictive Ionic Radii, MEFIR, as well as Charge Distribution, CHARDI, are calculated.  相似文献   

5.
Crystal Structures of the Polyselenides [Cs(18-Crown-6)]2Se5 · DMF, [Rb(222-Crypt)]2Se6, [Ba(15-Crown-5)2]Se6 · DMF, and [Na(12-Crown-4)2]Se7 . The title compounds have been prepared by reactions of the corresponding diselenides with excess selenium in the presence of crown ethers in dimethylformamide solutions, forming black crystals. [Cs(18-Crown-6)]2Se5 · DMF: Space group P21/m, Z = 2, 2 194 observed unique reflections, R = 0.119. Lattice dimensions at 20°C: a = 1 041.2; b = 1 496.3; c = 1 459.7 pm; β = 100.39°. The compound forms an ionic triple with Cs…Se-contacts between 374 and 381 pm. [Rb(222-Crypt)]2Se6: Space group P1 , Z = 2, 7 405 observed unique reflections, R = 0.056. Lattice dimensions at – 70°C: a = 1 106.8; b = 1 460.8; c = 1 718.8 pm; α = 89.22°; β = 86.65°; γ = 71.53°. The compound contains Se62? chains without direct contact with each other. [Ba(15-Crown-5)2]Se6 · DMF: Space group P21/n, Z = 4, 2 680 observed unique reflections, R = 0.055. Lattice dimensions at – 80°C: a = 1 051.9; b = 1 322.4; c = 2 729.9 pm; β = 100.93°. The compound contains Se62? chains, which are isolated from each other by the cations and the included DMF molecules. [Na(12-Crown-4)2]2Se7: Space group P1 , Z = 2, 7 313 observed unique reflections, R = 0.042. Lattice dimensions at – 70°C: a = 1 260.9; b = 1 433.6; c = 1 462.9 pm; α = 80.27°; β = 78.60°; γ = 69.34°. The compound contains Se72? chains without direct contacts with each other.  相似文献   

6.
Ternary Halides of the A3MX6 Type. III [1, 2]. Synthesis, Structures, and Ionic Conductivity of the Halides Na3MX6 (X = Cl, Br) The bromides Na3MBr6 crystallize with the stuffed LiSbF6-type structure (type I; M = Sm? Gd) or with the structure of the mineral cryolite (type II; M = Gd? Lu). The structure types were refined from single crystal X-ray data (Na3SmBr6: trigonal, space group R3 , a = 740.8(2) pm, c = 1 998.9(8) pm, Z = 3; Na3YBr6: monoclinic, space group P21/n, a = 721.3(4) pm, b = 769.9(2) pm, c = 1 074.8(4) pm, β = 90.60(4)°, Z = 2). Reversible phase transitions from one structure to the other occur. The phase transition temperatures were determined for the bromides as well as for the chlorides Na3MCl6 (M = Eu? Lu). The refinement of both structures for one compound was possible for Na3GdBr6 (I: trigonal, space group R3 , a = 737.1(5) pm, c = 1 887(2) pm, Z = 3; II: monoclinic, space group P21/n, a = 725.2(1) pm, b = 774.1(3) pm, c = 1 080.1(3) pm, β = 90.76(3)°, Z = 2). All compounds exhibit ionic conductivity of the sodium ions which decreases with the change from type I to type II. The conductivity of the bromides is always higher when compared with the respective chlorides.  相似文献   

7.
Crystal Structure Determinations of Four Monoclinic Weberites Na2MIIMIIIF7 (MII = Fe, Co; MIII = V, Cr) By solid state reaction of the binary fluorides single crystals of the following weberites were prepared and their monoclinic structure (space group C2/c, Z = 16) determined by X-ray methods: Na2FeVF7 (a = 1 271.0(3), b = 742.9(1), c = 2 471.6(5) pm, β = 100.03(3)°; R1 = 0.043 (1 545 Reflexe); Fe? F = 203.8, V? F = 193.0 pm); Na2FeCrF7 (a = 1 262.5(3), b = 739.1(1), c = 2 460.5(5) pm, β = 99.93(3)°; R1 = 0.029 (2 340); Fe? F = 203.6, Cr? F = 190.5 pm); Na2CoVF7 (a = 1 270.3(5), b = 739.1(3), c = 2 465.1(10) pm, β = 100.02(3)°; R1 = 0.028 (2 250); Co? F = 201.6, V? F = 193.6 pm); Na2CoCrF7 (a = 1 257.8(3), b = 733.5(1), c = 2 441.5(5) pm, β = 99.64(3)°; R1 = 0.030 (2 227); Co? F = 201.2, Cr? F = 190.2 pm). Concerning the above average distances within the distorted [MF6] octahedra and the shape of [NaF8] coordination details are given and discussed.  相似文献   

8.
Crystal Structure of Na5P3O10 · 6 H2O Na5P3O10 · 6 H2O crystallizes triclinic in P1 with a = 1 037.0(2), b = 984.8(4), c = 761.5(3) pm; α = 92.24(7)°, β = 94.55(9), γ = 90.87(6)°; Z = 2. The structure has been determined from fourcycle diffractometer data (2 089 independent reflections, R = 0.053). All hydrogen positions have been taken from a weighted difference-fourier-syntheses. Na5P3O10 · 6 H2O forms colorless, plate-like crystals, which are twinned systematically parallel (001) and can be divided mechanically into single-crystalline portions.  相似文献   

9.
Hydrogen Bonds in o- and m-Phenylenediammonium Aquapentafluoro Metallates(III) (MIII = Al, Cr, Fe) m- and o-Phenylenediammonium-[MIIIF5(H2O)] compounds of Al, Cr and Fe were synthesized and characterized by X-ray single crystal structure analysis. All structures are described in the space group P212121 (Z = 4). m-Ph(NH3)22+ (Ph(NH3)22+ = phenylenediammonium) compounds: Al : a = 6.489(2), b = 7.943(2), c = 18.204(2) Å, R/wR = 0.084/0.050 for 1 533 reflections; Cr : a = 6.571(2), b = 8.006(2), c = 18.456(3) Å, R/wR = 0.050/0.040 for 1 571 reflections; Fe : a = 6.608(2), b = 8.052(2), c = 18.424(4) Å, R/wR = 0.042/0.034 for 1 947 reflections. o-Ph(NH3)22+ compounds: Al : a = 6.580(2), b = 7.891(2), c = 18.319(5) Å, R/wR = 0.050/0.045 for 2 370 reflections; Cr : a = 6.642(2), b = 7.954(2), c = 18.484(4) Å, R/wR = 0.065/0.043 for 2 041 reflections; Fe : a = 6.693(2), b = 7.995(4), c = 18.529(7) Å, R/wR = 0.035/0.033 for 2 651 reflections. Isolated distorted octahedral [MIIIF5(H2O)]2? anions are connected by double O? H ?F hydrogen bonds of alternating strength to form chains in the b direction. Those chains, packed in a pseudohexagonal way, are further linked by the ammonium functions of the phenylenediammonium cations to a 3 D hydrogen bond network.  相似文献   

10.
Na2ZrS3: A Ternary Zirconium Sulfide with Stuffed AlCl3‐type Structure Dark green, plate‐like single crystals of Na2ZrS3 (monoclinic, C2/m; a = 664.69(6), b = 1152.5(1), c = 695.48(7) pm, β = 108.78(1)°; Z = 4) are obtained along with pale yellow platelets of NaZr2N2SCl (trigonal, R3m; a = 363.56(3), c = 2951.2(4) pm; Z = 3) upon oxidation of zirconium metal with sulfur and sodium azide (NaN3) in the presence of fluxing NaCl (molar ratio 7:6:2:3) in evacuated silica tubes at 850°C within three weeks. The crystal structure is best described as stuffed AlCl3 type with all cations (Na+ and Zr4+) in octahedral coordination of the S2– anions, which build up a cubic closest packed host lattice. The internuclear metal sulfur distances range from 276 to 296 pm for all three crystallographically different Na+ cations, and from 258 to 260 pm for Zr4+.  相似文献   

11.
Chelates of 8-Quinolinol Derivatives. XII. Crystal and Molecular Structure of Bis(7-isopropyl-8-quinolinato)nickel(II) The crystal and molecular structure of bis(7-isopropyl-8-quinolinato)nickel(II) was determined by X-ray diffraction. The structure is monoclinic with the space group P21/n (Z = 2, 1403 observed independent reflections, R = 0.049. Lattice dimensions at 20°C: a = 1328.3(5) pm, b = 632.8(2) pm, c = 1330.0(5) pm, β = 112.99(3)°). The coordination of the nickel atom is planar with the quinoline rings in trans position.  相似文献   

12.
The Crystal Structures of the Vanadium Weberites Na2MIIVIIIF7 (MII ? Mn, Ni, Cu) and of NaVF4 At single crystals of the vanadium(III) compounds NaVF4 (a = 790.1, b = 531.7, c = 754.0 pm, β = 101.7°; P21/c, Z = 4), Na2NiVF7 (a = 726.0, b = 1031.9, c = 744.6 pm; Imma, Z = 4) and Na2CuVF7 (a = 717.6, b = 1043.5, c = 754.6 pm; Pmnb, Z = 4) X-ray structure determinations were performed, at Na2MnVF7 (a = 746.7, c = 1821.6 pm; P3221, Z = 6) a new refinement. NaVF4 crystallizes in the layer structure type of NaNbO2F2. The fluorides Na2MIIVF7 represent new orthorhombic (MII ? Ni; Cu) resp. trigonal (MII ? Mn) weberites. The average distances within the [VF6] octahedra of the four compounds are in good agreement with each other and with data of related fluorides (V? F: 193.3 pm). The differences between mean bond lengths of terminal and bridging F ligands are 5% in NaVF4, but less than 1% in the weberites. Details and data for comparison are discussed.  相似文献   

13.
Preparation and Crystal Structure of the First Mixed Alkalimetal Hydrogencarbonates NaA2[H(CO3)2] · 2H2O with A = K, Rb The new hydrogencarbonates NaK2[H(CO3)2] · 2H2O (Pnma, a = 934.07(13) pm, b = 789.31(10) pm, c = 1142.1(5) pm, VEZ = 842.0(4) · 106 pm3, Z = 4, R1 (I ? 2σ(I)) = 0.023, wR2 = 0.066 for 989 reflections) and NaRb2[H(CO3)2] · 2H2O (Pnma, a = 948.24(11) pm, b = 811.37(9) pm, c = 1189.0(2) pm, VEZ = 914.8(2) · 106 pm3, Z = 4, R1 (I ≤ 2σ(I)) = 0.031, wR2 = 0.077 for 1063 reflections) were prepared from aqueous solutions. The crystal structures were determined. The isostructural compounds contain dimeric, non centrosymmetric [H(CO3)2]3? anions. In NaK2[H(CO3)2] · 2H2O a short hydrogen bond (d(O … O) = 246.1(2) pm) with an asymmetric potential was detected. In NaRb2[H(CO3)2] · 2H2O a hydrogen bond with symmetric potential (d(O … O) = 247.8(5) pm) can be assumed. The IR-spectra of NaK2[H(CO3)2] · 2H2O and Na3[H(CO3)2] · 2H2O are compared.  相似文献   

14.
The crystal and molecular structures have been determined by single-crystal X-ray methods for the binuclear metal ions (II) complexes of 7-azaindole (1H-pyrrolo [2,3-b] pyridine, C7H6N2 denoted by HL), Cu2(CH3CO2)2.·L2(HL)2 and Ni2L4.2DMF. The dark green crystal of Cu2(CH3CO2)2L2(HL)2 was found to crystallize in the monoclinic space group P 21/n with a = 9.566(2), b = 12.752(2), c = 12.852(4) Å, β = 99.23(3)0, V = 1547 Å, Z = 2, the final R = 0.062 and Rw = 0.053 for 1488 observations from 2722 unique reflections. The Cu-Cu distance is 2.747(2), Cu-N (L?, bridge) is 1.966(7), Cu-N (HL, axial) is 2.229(8), and Cu-O is 2.031(6)Å. The red crystal of Ni2L4.2DMF was was found to crystallize in the triclinic space group \documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm P \bar 1} $$\end{document} with a = 8.907(5), b = 9.462(2), c = 10.217(2) Å, α = 90.48(2), β = 91.09(3), γ = 110.69(3)0, V =805 Å3, Z = 1, the final R = 0.063 and Rw = 0.069 for 1489 observations from 2834 unique reflections. The Ni-Ni distance is 2.594(2), Ni-N is 1.905(7) Å. These two molecules lie on crystllographic inversion centers and exhibit ligand disorder.  相似文献   

15.
Structure and Electrochemical Study of Nb3Cl8 The compound Nb3Cl8 was synthesized from NbCl5 and niobium metal in a sealed quartz ampoule at 700 °C. Single crystals, obtained from LiCl melt were used for X‐ray structure determination (space group P 3 m1, Z = 2, lattice parameters a = b = 672.95(7) pm, c = 1223.2(2) pm (at 100 K), R1 = 0.029, wR2 = 0.064 for all independent reflections). Electrical resistivity measurements are reported. Electrochemical intercalation of lithium into the structure of Nb3Cl8 was studied.  相似文献   

16.
A Sodium‐Oxocobaltate(II)‐Hydroxide: Na5[CoO3]OH ≡ Na10[CoO3]{[CoO3](OH)2} Na10[CoO3]{[CoO3](OH)2} has been obtained from a redox reaction between cobalt metal and CdO in the presence of NaOH and Na2O at 600 °C (21 d) as red single crystals. The structure has been determined from single crystal data (IPDS‐data, Pnma, Z = 4, a = 988.5(1) pm, b = 1013.9(2) pm, c = 1186.3(2) pm, wR2 = 0.079). Furthermore IR data and aspects of the Madelung part of the lattice energy are presented.  相似文献   

17.
Cp2YbCl(THF) crystallizes in the orthorhombic space group Pnma (Z = 4, a = 13.109(5), b = 11.851(4), c = 9.377(3) Å, R1 = 0.0412, wR2 = 0.0482), while Cp2YbBr(THF) is monoclinic (P21/n, Z = 4, a = 8.149(2), b = 12.997(2), c = 14.388(3) Å, β = 105.73(2)°, R1 = 0.0425, wR2 = 0.0436). The ligand arrangements around the formally eight coordinate Yb atoms are pseudo tetrahedral. These two determinations complete the first series of [Cp2LnX(L)] (X = F, Cl, Br, I) structures covering all halogens for one lanthanoid and cyclopentadienyl group.  相似文献   

18.
Ln6(mu6-O)(mu3-OH)8(H2O)24]I8(H2O)(8) (Ln = Nd, Eu, Tb, Dy) compounds are obtained as the final hydrolysis products of lanthanide triiodides in an aqueous solution. Their X-ray crystal structure features a body-centered arrangement of oxygen-centered {Ln6X8}8+ cluster cores: [Nd6(mu6-O)(mu3-OH)8(H2O)24]I8(H2O)8 [Pearson code oP156, orthorhombic, Pnnm (No. 58), Z = 2, a = 1310.4(3) pm, b = 1502.1(3) pm, c = 1514.9(3) pm, 3384 reflections with I0 > 2sigma(I0), R1 = 0.0340, wR2 = 0.0764, GOF = 1.022, T = 298(2) K], [Eu6(mu6-O)(mu3-OH)8(H2O)24]I8(H2O)8 [Pearson code oP156, orthorhombic, Pnnm (No. 58), Z = 2, a = 1306.6(2) pm, b = 1498.15(19) pm, c = 1499.41(18) pm, 4262 reflections with I0 > 2sigma(I0), R1 = 0.0540, wR2 = 0.0860, GOF = 0.910, T = 298(2) K], [Tb6(mu6-O)(mu3-OH)8(H2O)24]I8(H2O)8 [Pearson code oP156, orthorhombic, Pnnm (No. 58), Z = 2, a = 1296.34(5) pm, b = 1486.13(7) pm, c = 1491.88(6) pm, 4182 reflections with I0 > 2sigma(I0), R1 = 0.0395, wR2 = 0.0924, GOF = 1.000, T = 298(2) K], and [Dy6(mu6-O)(mu3-OH)8(H2O)24]I8(H2O)8 [Pearson code oP156, orthorhombic, Pnnm (No. 58), Z = 2, a = 1296.34(5) pm, b = 1486.13(7) pm, c = 1491.88(6) pm, 3329 reflections with I0 > 2sigma(I0), R1 = 0.0389, wR2 = 0.0801, GOF = 0.992, T = 298(2) K.  相似文献   

19.
On Na2PrO3 and Na2TbO3 Using an exchange reaction of Na2O with Li8TbO6 (Na : Tb = 2.1 : 1; au-tube; 750°C, 30 d) yellow-orange colored single crystals of Na2TbO3 could be prepared for the first time. Na2TbO3 crystallizes monoclinic in C2/c (Z = 8; a = 576.92(6), b = 1001.27(9), c = 1117.91(14) pm, β = 99.98(1)°). According to four-circle data the Li2SnO3-type of structure is adopted (PW 1100, MoKα , 1935 I0 (hkl), R = 4.86%, Rw = 3.63% for all 928 unique reflexions). By a similar exchange reaction of Na2O with Li8PrO6 for the first time single crystals of Na2PrO3 could be prepared, too (Na : Pr = 2.2 : 1; au-tube; 700°C; 23 d). The structure determination reveils that there is a variant of the NaCl-type of structure, which ressembles to the Li2SnO3-type of structure (PW 1100, MoKα , 2199 I0 (hkl)), R = 8.88%, Rw = 5.21% for all 947 unique reflexions; C2/c, Z = 8, a = 678.78(5), b = 977.47(7), c = 1080.38(9) pm, β = 108,4(1)°. In contrast to Na2TbO3 there are no layers according to NaO(Na1/3Tb2/3)O. All octahedral intersticies are occupied systematically with Pr4+ and Na+ : (Na2/3Pr1/3)O(Na2/3Pr1/3)O.  相似文献   

20.
New Phosphorus-bridged Transition Metal Complexes The Crystal Structures of [Co4(CO)10(PiPr)2], [Fe3(CO)9(PtBu)(PPh)], [Cp3Fe3(CO)2(PPtBu)· (PtBu)], [(NiPPh3)2(PiPr)6], [(NiPPh3)Ni{(PtBu)3}2], and [Ni8(PtBu)6(PPh3)2] By the reaction of cyclophosphines with transition metal carbonyl-derivatives polynuclear complexes are built, in which the PR-ligands (R = organic group) are bonded in different ways to the metal. Depending on the reaction conditions the following compounds can be characterized: [Co4(CO)10 · (PiPr)2] ( 2 ), [Fe3(CO)9(PtBu)(PPh)] ( 3 ), [Cp3Fe3(CO)2(PPtBu) · (PtBu)] ( 4 ), [(NiPPh3)2(PiPr)6] ( 5 ), [(NiPPh3)Ni{(PtBu)3}2] ( 6 ) and [Ni8(PtBu)6(PPh3)2] ( 7 ). The structures of 2–7 were obtained by X-ray single crystal structure analysis ( 2 : space group Pccn (No. 56), Z = 4, a = 1001,4(2) pm, b = 1375,1(3) pm, c = 1675,5(3) pm; 3 : space group P21 (No. 4), Z = 2, a = 914,3(4) pm, b = 1268,7(4) pm, c = 1028,2(5) pm, β = 101,73(2)°; 4 : space group P1 (No. 2), Z = 2, a = 946,0(5) pm, b = 1074,4(8) pm, c = 1477,7(1,0) pm, α = 107,63(5)°, β = 94,66(5)°, γ = 111,04(5)°; 5 : space group P1 (No. 2), Z = 2, a = 1213,6(2) pm, b = 1275,0(2) pm, c = 2038,8(4) pm, α = 92,810(10)°, β = 102,75(2)°, γ = 93,380(10)°; 6 : space group P1 (No. 2), Z = 2, a = 1157,5(5) pm, b = 1371,9(6) pm, c = 1827,6(10) pm; α = 69,68(3)°, β = 80,79(3)°, γ = 69,36(3)°; 7 : space group P3 (No. 147), Z = 1, a = 1114,1(2) pm, b = 1114,1(2) pm, c = 1709,4(3) pm).  相似文献   

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