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1.
Li2I(OH): A Compound with Onedimensional Infinite Edge Sharing [Li4/2(OH)+] Pyramids The pseudobinary system LiOH/LiI was investigated by X-ray methods. Two compounds, Li2I(OH) and Li5I(OH)4 exist. The structure of Li2I(OH) was solved by single-crystal data. For Li5I(OH)4 lattice constants and space group symmetry are given: Li2I(OH): Pnma, Z = 4, a = 10.339(4) Å, b = 5.567(1) Å, c = 6.643(2) Å, Z(Fo) mit (Fo)2 ≧ 3σ(Fo)2 = 439, Z (parameter) = 23, R/Rw = 0.030/0.040 Li5I(OH)4: Pmmn or P21mn(= Pmn21), Z = 2, a = 10.42 Å, b = 5.30 Å, c = 5.81 Å Li2I(OH) crystallizes in a new type of structure. The motif of a distorted hexagonal close-packed arrangement of iodide ions is penetrated by chains of [Li4/2(OH)+].  相似文献   

2.
A series of oxygen-defect perovskites, containing CuII and CuIII, La3Ba3 [CuII5?2y CuIII1+2y] O14+y, has been synthesized at 1000°C, for 0.05 ≤ y ≤ 0.43. The substitution of lanthanum for yttrium and lanthanides has been studied. These oxides are tetragonal: a = ap 212 and c = 3ap. The structural study of La3Ba3 Cu6O14.10 shows that oxygen vacancies are ordered, involving for copper three sorts of coordination: square, pyramidal (4 + 1), and distorted octahedral (4 + 2). The distribution of CuIII, as well as the lanthanide ions on the different sites, is discussed.  相似文献   

3.
An Oxygen-rich Neodymium Cuprate: High-pressure Synthesis and Crystal Structure of Nd12Cu6O25 (“Nd2CuO4.17”) Single crystals of Nd12Cu6O25 (“Nd2CuO4.17”) could be obtained by reaction of Nd2O3 und CuO with KO2 in a modified Belt-type apparatus at 40 kbar, 1500°C. The compound crystallizes in the monoclinic space group C2/m with a = 17.128(6), b = 3.7288(6), c = 18.364(6) Å, β = 111.22(1)º and Z = 2. The structure refinement converged at R1 = 0.0302 for 1451 reflections with Fo > 4σ(Fo) and R1 = 0.0903, wR2 = 0.0767 for all 2571 data. The structure-determining feature are Cu(1,2)? O octahedral chains, interrupted by Cu(3) atoms in square-planar coordination. Each of this CuO4 groups is connected to another one, resulting in short copper-copper distances (dCu? Cu = 3.012 Å). A comparison of the structure of “Nd2CuO4.17” with those of La2CuO4 and Nd2CuO4 makes the structural relations of the former with La2CuO4 and, hence, the aristotype K2NiF4 evident, in spite of the close stoichiometric similarity between Nd2CuO4 and “Nd2CuO4.17”.  相似文献   

4.
The metathetical reactions of a) [Li(tmeda)]2[(S)C(PPh2S)2] (Li2? 3 c ) with CuCl2 and b) [Li(tmeda)]2[(SPh2P)2CSSC(PPh2S)2] (Li2? 4 c ) with two equivalents of CuCl both afford the binuclear CuI complex {Cu2[(SPh2P)2CSSC(PPh2S)2]} ( 5 c ). The elongated (C)S? S(C) bond (ca. 2.54 and 2.72 Å) of the dianionic ligand observed in the solid‐state structure of 5 c indicate the presence of diradical character as supported by theoretical analyses. The treatment of [Li(tmeda)]2[(SPh2P)2CSeSeC(PPh2S)2] (Li2? 4 b ) and Li2? 4 c with AgOSO2CF3 produce the analogous AgI derivatives, {Ag2[(SPh2P)2CEEC(PPh2S)2]} ( 6 b , E=Se; 6 c , E=S), respectively. The diselenide complex 6 b exhibits notably weaker Ag? Se(C) bonds than the corresponding contacts in the CuI congeners, and the 31P NMR data suggest a possible isomerization in solution. In contrast to the metathesis observed for CuI and AgI reagents, the reactions of Li2? 4 b and Li2? 4 c with Au(CO)Cl involve a redox process in which the dimeric dichalcogenide ligands are reduced to the corresponding monomeric dianions, [(E)C(PPh2S)2]2? ( 3 b , E=Se; 3 c , E=S), and one of the gold centers is oxidized to generate the mixed‐valent AuI/AuIII complexes, {Au[(E)C(PPh2S)2]}2 ( 7 b , E=Se; 7 c , E=S), with relatively strong aurophilic AuI???AuIII interactions. The new compounds 5 c , 6 b , c and 7 b , c are characterized in solution by NMR spectroscopy and in the solid state by X‐ray crystallography ( 5 c , 6 b , 7 b and 7 c ) and by Raman spectroscopy ( 5 c and 6 c ). The UV‐visible spectra of coinage metal complexes of the type 5 , 6 and 7 are discussed in the light of results from theoretical analyses using time‐dependent density functional theory.  相似文献   

5.
The isostructural compounds Yb2MgSi2, La2.05Mg0.95Si2, and Ce2.05Mg0.95Si2, as well as Yb2Li0.5Ge2 and Yb1.75Mg0.75Si2, respectively, were synthesized from stoichiometric mixtures of the corresponding elements in sealed Nb‐ ampoules under argon atmosphere. The structures were determined by single crystal X‐ray diffraction: Yb2MgSi2 (P4/mbm (No. 127), a = 7.056(1), c = 4.130(1) Å3, Z = 2), La2.05Mg0.95Si2 (P4/mbm, a = 7.544(1), c = 4.464(1) Å3, Z = 2), and Ce2.05Mg0.95Si2 (P4/mbm, a = 7.425(1), c = 4.370(1) Å3, Z = 2), Yb2Li0.5Ge2 (Pnma (No. 62), a = 7.0601(6), b = 14.628(1), c = 7.6160(7) Å, V = 786.5Å3, Z = 4), Yb1.75Mg0.75Si2 (Pnma, a = 6.9796(1), b = 14.4009(1), c = 7.5357(1) Å, V = 757.43(2) Å3, Z = 4). All compounds contain exclusively Tt‐Tt dumb‐bells (Tt = Si, Ge). The Si‐Si Zintl anions exhibit only very small variations of bond lengths which seem to be more due to cation matrix effects than to effective bond orders.  相似文献   

6.
Syntheses, Crystal Structures, and Properties of Ln4Au2O9 (Ln = Nd, Sm, Eu) The compounds Ln4Au2O9 (Ln = Nd, Sm, Eu) have been prepared from amorphous Au2O3 · 2–3 H2O and Ln2O3 (Ln = Nd, Sm, Eu) via solid state reaction under elevated oxygen pressure adding KOH as mineralising agent. They are isostructural with La4Au2O9 (Nd4Au2O9: a = 11.9813(3), b = 6.1474(1), c = 11.9641(4); 453 powder intensities, Rp = 3.75%; Sm4Au2O9: a = 11.8689(4), b = 6.0360(1), c = 11.8469(4) Å; 812 unique reflections, R1 = 2.75%; Eu4Au2O9: a = 11.8241(3), b = 5.9922(1) Å, c = 11.8013(3) Å; 1315 unique reflections, R1 = 7.83%). The crystal structure of Nd4Au2O9 was refined from powder diffraction data. The structures of Sm4Au2O9 and Eu4Au2O9 were solved and refined from single crystal data. The isolated square planar AuO4 units are stacked as columns and are linked to each other by LnO7‐polyhedra. One of the oxygen atoms is exclusively connected to the trivalent lanthanides in tetrahedral geometry. Ln4Au2O9, Bi2CuO4, Bi2AuO5 and Bi4Au2O9 are closely related, structurally. The lanthanoid aurates decompose between 700 and 800 °C into Ln2O3, Au and O2. The effective magnetic moments 3.64 μB (Nd4Au2O9), 1.7 μB (Sm4Au2O9) and 3.3 μB (Eu4Au2O9) confirm that the lanthanides are trivalent. The UV/VIS absorption spectra can be interpreted at assuming free ions.  相似文献   

7.
A novel two‐dimensional 3d–4f heterometallic inorganic compound with the formula [CuII3GdIII3‐OH)63‐SH)(SO4)(H2O)3] ( 1 ) was synthesized by treating gadolinium nitrate, copper chloride and DTSA under hydrothermal conditions. The structure was determined by X‐ray crystallography. The crystal is of orthorhombic, space group P212121 with a = 6.63090(1) Å, b = 11.3145(3) Å, c = 15.7869(3) Å, Cu3GdH13O13S2, M = 633.09, Z =4, V = 1184.42(4) Å3, F(000) = 1200, R1 = 0.0244 and ωR = 0.0522. The solid‐state dc magnetic susceptibility measurements revealed antiferromagnetic interactions between the paramagnetic metal center ions.  相似文献   

8.
The single phase La1-x NaxCu2O4 crystals were synthesized by an electrochemical method from molten KOH/NaOH/KNO3 at 280-300℃ while La2-yNayCuO4 were prepared by precipitation from the same molten salt. The resulting crystals were characterized by using SEM, XRD, EDX and XPS. XPS analysis revealed that the La3d satellite structures of La1-xNaxCu2O4 were quite different from those of La2-yNayCuO4. These differences have been attributed to the changes in crystal structures, bond lengths and covalent character of the metal-ligand bonds.  相似文献   

9.
AuF3 is reduced in superacidic HF/SbF5 solutions giving three products. 1. Orange [Au3F8·2SbF5]. It has a layered structure built up by square planar AuIIF4 and AuIIIF4 units: Crystal structure: space group P21/c, a = 9.049(2), b = 8.424(1), c = 9.645(1)Å, β = 115.08(1)°. 2. Black [Au3F7·3SbF5] has a ribbon structure, similarly built up by square planar AuIIF4 and AuIIIF4 units: Crystal structure: space group Pc, a = 9.991(1), b = 10.728(1), c = 15.222(1)Å, β = 95.304(2)°. 3. Yellow green [(Au(HF)2] (SbF6)2·2HF with square planar AuIIF4 units that are formed by two fluorine atoms of the anions and two HF molecules as complex ligands. Crystal structure: Space group P¯, a = 5.482(1), b = 5.848(1), c = 9.309(2)Å, α = 89.522(4), β = 85.635(4), γ = 87.509(4)°.  相似文献   

10.
Preparation and Crystal Structure of Potassium Magnesium Oxocuprate/-vanadate: KMg2Cu2V3O12 . Single crystals of KMg2Cu2V3O12 were prepared by solid state reactions below the melting point of the reaction mixture (K2CO3, MgCO3, CuO, V2O5). It crystallizes with monoclinic symmetry space group C? C2/c, a = 12.1592 Å, b = 12.7204 Å, c = 6.8557 Å, β = 111.73°, Z = 4. The structure type is characterized by VO4 tetrahedra, twisted CuO4 square units, MgO6 octahedra and a special 2 + 4 + 2 coordination around the potassium ion.  相似文献   

11.
La2O(CN2)2 was synthesized from a 1:1:2 molar reaction mixture of LaCl3, LaOCl, and Li2(CN2) at 650 °C. Well developed single crystals were grown from a LiCl‐KCl flux. The crystal structure was refined as monoclinic (space group C2/c, Z = 2, a = 13.530(2) Å, b = 6.250(1) Å, c = 6.1017(9) Å, β = 104.81(2)°) from single crystal X‐ray diffraction data. The La3+ and (CN2)2— ions in the crystal structure of La2O(CN2)2 can be compared to Fe3+ and S22— ions in the cubic pyrite structure, being arranged like in a distorted NaCl type structure with their centers of gravity. In addition, the O2— ions in La2O(CN2)2 are occupying 1/4 of the tetrahedral voids formed by the arrangement of metal ions.  相似文献   

12.
The new compounds K2Au2Ge2S6 ( 1 ), K2Au2Sn2Se6 ( 2 ), and Cs2Au2SnS4 ( 3 ) have been synthesized through direct reaction of the elements with a molten polyalkalithiogermanate(stannate) flux at 650, 550, and 400 °C, respectively. Their crystal structures have been determined by single crystal X-ray diffraction techniques. 1 crystallizes in the monoclinic space group P21/n with a = 10.633(2) Å, b = 11.127(2) Å, c = 11.303(2) Å, β = 115,37(3)°, V = 1208,2(3) Å3 and Z = 4, final R(Rw) = 0.045(0.106). 2 crystallizes in the tetragonal space group P4/mcc with a = 8.251(1) Å, c = 19.961(4) Å, V = 1358,9(4) Å3 and Z = 4, final R(Rw) = 0.040(0.076). 3 crystallizes in the orthorhombic space group Fddd with a = 6.143(1) Å, b = 14.296(3) Å, c = 24.578(5) Å, V = 2158.4(7) Å3 and Z = 4, final R(Rw) = 0.039(0.095). The structures of 1 , 2 , and 3 consist of infinite, one-dimensional anionic chains containing X2Q64– units linked by Au+ ions and charge balancing K+/Cs+ ions situated between the chains. All compounds were investigated with differential thermal analysis, FT-IR, and solid state UV/VIS diffuse reflectance spectroscopy.  相似文献   

13.
Structural Investigations on the Oxidenitrides SrTaO2N, CaTaO2N and LaTaON2 by Neutron and X‐ray Powder Diffraction The crystal structures of the perovskite related oxidenitrides SrTaO2N, LaTaON2 and CaTaO2N have been determined with special regard to the structures of the respective anionic partial structure. The structure refinements were performed by individual Rietveld analyses of both X‐ray and neutron powder diffractograms and in addition by joint refinements in order to confirm the results. Both refinement methods yield consistent structure solutions. At least the first two compounds have fully ordered anionic sublattices. The crystal structure of SrTaO2N has been solved in the space group I4/mcm (a = 5.7049(3) Å, c = 8.0499(5) Å, Rp = 0.0706, Rwp = 0.0904, reflections: 70 (neutrons)/36 (X‐ray), R(F2)(n) = 0.147, R(F2)(X) = 0.0952), with an ordered anionic partial structure. LaTaON2 crystallizes monoclinic (C2/m, a = 8.0922(3) Å, b = 8.0603(2) Å, c = 5.7118(2) Å, β = 134.815(1)°, Rp = 0.0592, Rwp = 0.0766, reflections: 235(n)/113(X), R(F2)(n) = 0.0944, R(F2)(X) = 0.165) and also shows a totally ordered distribution of the anions. In the case of CaTaO2N (Pnma, a = 5.6239(3) Å, b = 7.8954(4) Å, c = 5.5473(3) Å, Rp = 0.0503, Rwp = 0.0656, reflections 206(n)/110(X), R(F2)(n) = 0.0985, R(F2)(X) = 0.0405) slightly unbalanced displacement parameters (neutron data, ordered O/N distribution model) hint at a partial exchange of oxygen and nitrogen.  相似文献   

14.
Herein we report synthesis of a new brucite type copper hydroxide squarate, Cu3(OH)2(C4O4)2·4H2O [P21/c, a = 5.6437(4) Å, b = 12.8357(9) Å, c = 9.1507(6) Å, β = 95.892(1)° and Z = 2] by hydrothermal method, and its characterization by single crystal diffraction analysis as well as by IR spectroscopy. The rather wide spread of Cu–O bond lengths, can be primarily rationalised by the Jahn‐Teller effect, and secondarily by the connectivities of the CuO6 octahedra.  相似文献   

15.
On Alkaline Earth Oxocuprates VIII. About Sr2CuO2Cl2 Sr2CuO2Cl2 was prepared and investigated by single crystal X – ray work (space group D–Immm, a = 3.975, c = 15.618 Å). Sr2CuO2Cl2 is isotypic with K2NiF4 – compounds and shows an octahedral configuration for Cu2+. Cl? occupies trans-positions of the octahedral Cu2+/O2? polyhedron. A discussion with related compounds (Sr2CuO3 and Nd2CuO4) explains the observed distribution of O2? and Cl?.  相似文献   

16.
LLi2Mo4o13 crystallizes in the triclinic system with unit-cell dimensions a = 8.578 Å, b = 11.450 Å, c = 8.225 Å, α = 109.24°, β = 96.04°, γ = 95.95° and space group P1, Z = 3. The calculated and measured densities are 4.02 g/cm3 and 4.1 g/cm3 respectively. The structure was solved using three-dimensional Patterson and Fourier techniques. Of the 2468 unique reflections collected by counter methods, 1813 with I ? 3σ(I) were used in the least-squares refinement of the model to a conventional R of 0.031 (ωR = 0.038). LLi2Mo4O13 is a derivative of the V6O13 structure with oxygen ions arranged in a face-centred cubic type array with octahedrally coordinated molybdenum and lithium ions ordered into layers.  相似文献   

17.
Na7Cu3O8 was prepared through oxidation of a Na3CuO2/NaCuO mixture (2:1) in dried oxygen at 450 °C. Single crystals have been grown by annealing of Na7Cu3O8, in the presence of Na2O2, at 450 °C for 2000 h in silver crucibles, which were sealed in glass ampoules under dried Ar. According to the X-ray analysis of the crystal structure ( , Z = 1, a = 5.5891(2), b = 6.0945(2), c = 7.8890(3) Å, α = 110.059(2), β = 108.669(2), γ = 90.237(2)°) a new Cu3O87- oxocuprate anion, consisting of three edge sharing CuO4 squares, is the prominent structural feature. These anions are aligned parallel to the space diagonal of the unit cell and can be regarded as infinite chains from which every fourth copper atom has been removed. This new representative of an oxocuprate(III) anion gives support to the expectation that the gap between dimeric and infinite edge sharing units of square planar cuprate anions can be closed, in principle.  相似文献   

18.
Li2Br(NH2): The First Ternary Alkali Metal Amide Halide The pseudobinary system LiNH2/LiBr was investigated by X-ray methods. The crystal structure of the compound Li2Br(NH2) was solved by single crystal data: Li2Br(NH2): Pnma, Z = 8, a = 12.484(2) Å, b = 7.959(1) Å, c = 6.385(1) Å, Z(Fo) with (Fo)2 ≧ 3σ(Fo)2 = 348, Z (parameter) = 51, R/Rw = 0.019/0.021 Li2Br(NH2) crystallizes in a new type of structure. To one another isolated chains of [Li2Li4/2(NH2)22+] show the motif of closest rod packing. They are connected via bromide ions in a distorted cubic primitive arrangement.  相似文献   

19.
Unusual Coordination Polyhedra around Oxygen in Li4Cl(OH)3 The pseudobinary system LiOH/LiCl was investigated by X-ray methods. Two compounds, Li4Cl(OH)3 and Li2Cl(OH), were obtained. The crystal structure of Li4Cl(OH)3 solved by single-crystal methods is delt with. For Li2Cl(OH) powder diffraction data are given: Li4Cl(OH)3: P21/m, Z = 2, a = 5.4096(8) Å, b = 7.382(2) Å, c = 6.2076(8) Å, β = 94.40(1)°, Z(Fo) with (Fo)2 ≧ 3σ(Fo)2 = 483, Z (parameter) = 50, R/Rw = 0.022/0.025 Li2Cl(OH): Pmma, Z = 2, a = 7.680(8) Å, b = 4.001(7) Å, c = 3.899(6) Å The hydroxide rich compound crystallizes in a new type of structure which contains puckered layers [Li4(OH)3+] connected via chloride ions.  相似文献   

20.
The crystal structures of chromium and indium dihydrogen triphosphates, CrH2P3O10 and InH2P3O10, in modification II are refined by the Rietveld method using X-ray powder diffraction data. The compounds crystallize in the monoclinic crystal system, space group P21/n. Z = 4, a = 7.3225(4)Å, b = 8.6835(6)Å, c = 11.6599(7) Å, and b = 102.388(3)° for CrH2P3O10, and a = 7.5332(1)Å, b = 9.0841(1)Å, c = 11.8600(1) Å, and b = 103.9596(7)° for InH2P3O10. The structures are refined in the isotropic approximation (pseudo-Voigt profile function): Rp = 4.8%, Rwp = 6.9%, RBragg = 7.5%, RF = 9.9% for CrH2P3O10; Rp = 6.3%, Rwp = 8.3%, RBragg = 6.2%, RF = 4.1% for InH2P3O10. The crystal structures of compounds in the isostructural series MIIIH2P3O10-II, where MIII = Al, Ga, Cr, V, Fe, and In, are examined and compared.  相似文献   

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