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1.
An Anionic Oxohydroxo Complex with Bismuth(III): Na6[Bi2O2(OH)6](OH)2 · 4H2O Colourless, plate‐like, air sensitive crystals of Na6[Bi2O2(OH)6](OH)2 · 4H2O are obtained by reaction of Bi2O3 or Bi(NO3)3 · 5H2O in conc. NaOH (58 wt %) at 200 °C followed by slow cooling to room temperature. The crystal structure (triclinic, P 1¯, a = 684.0(2), b = 759.8(2), c = 822.7(2) pm, α = 92.45(3)°, ß = 90.40(3)°, γ = 115.60(2)°, Z = 1, R1, wR2 (all data), 0, 042, 0, 076) contains dimeric, anionic complexes [Bi2O2(OH)6]4— with bismuth in an ψ1‐octahedral coordination of two oxo‐ and three hydroxo‐ligands. The thermal decomposition was investigated by DSC/TG or DTA/TG and high temperature X‐ray powder diffraction measurements. In the final of three steps the decomposition product is Na3BiO3.  相似文献   

2.
The crystal structures of Na2Mg3(OH)2(SO4)3 · 4H2O and K2Mg3(OH)2(SO4)3 · 2H2O, were determined from conventional laboratory X‐ray powder diffraction data. Synthesis and crystal growth were made by mixing alkali metal sulfate, magnesium sulfate hydrate, and magnesium oxide with small amounts of water followed by heating at 150 °C. The compounds crystallize in space group Cmc21 (No. 36) with lattice parameters of a = 19.7351(3), b = 7.2228(2), c = 10.0285(2) Å for the sodium and a = 17.9427(2), b = 7.5184(1), c = 9.7945(1) Å for the potassium sample. The crystal structure consists of a linked MgO6–SO4 layered network, where the space between the layers is filled with either potassium (K+) or Na+‐2H2O units. The potassium‐bearing structure is isostructural to K2Co3(OH)2(SO4)3 · 2(H2O). The sodium compound has a similar crystal structure, where the bigger potassium ion is replaced by sodium ions and twice as many water molecules. Geometry optimization of the hydrogen positions were made with an empirical energy code.  相似文献   

3.
Crystal Structures of Sr(OH)2 · H2O, Ba(OH)2 · H2O (o.-rh. and mon.), and Ba(OH)2 · 3 H2O The crystal structures of Ba(OH)2 · 3 H2O (Pnma, Z = 4), γ-Ba(OH)2 · H2O (P21/m, Z = 2) and the isotypic Sr(OH)2 · H2O and β-Ba(OH)2 · H2O (Pmc21, Z = 2) were determined using X-ray single crystal data. Ba(OH)2 · 3 H2O and Ba(OH)2 · H2O mon. crystallize in hitherto unknown structure types. The structure of Ba(OH)2 · H2O mon. is strongly related to that of rare earth hydroxides M(OH)3 with space group P63/m (super group of P21/m). The metal-oxygen distances are significantly shorter for OH? ions (mean Ba—O bond lengths of all hydroxides under investigation 278.1 pm) than for H2O molecules (289.9 pm). Corresponding to other hydrates of ionic hydroxides, the water molecules form strong hydrogen bonds to adjacent OH? ions whereas the hydroxide are not H-bonded.  相似文献   

4.
Two uranyl sulfate hydrates, (H3O)2[(UO2)2(SO4)3(H2O)] · 7H2O (NDUS) and (H3O)2[(UO2)2(SO4)3(H2O)] · 4H2O (NDUS1), and one uranyl selenate‐selenite [C5H6N][(UO2)(SeO4)(HSeO3)] (NDUSe), were obtained and their crystal structures solved. NDUS and NDUSe result from reactions in highly acidic media in the presence of L ‐cystine at 373 K. NDUS crystallized in a closed vial at 278 K after 5 days and NDUSe in an open beaker at 278 K after 2 weeks. NDUS1 was synthesized from aqueous solution at room temperature over the course of a month. NDUS, NDUS1, and NDUSe crystallize in the monoclinic space group P21/n, a = 15.0249(4) Å,b = 9.9320(2) Å, c = 15.6518(4) Å, β = 112.778(1)°, V = 2153.52(9) Å3,Z = 4, the tetragonal space group P43212, a = 10.6111(2) Å,c = 31.644(1) Å, V = 3563.0(2) Å3, Z = 8, and in the monoclinic space group P21/n, a = 8.993(3) Å, b = 13.399(5) Å, c = 10.640(4) Å,β = 108.230(4)°, V = 1217.7(8) Å3, Z = 4, respectively.The structural units of NDUS and NDUS1 are two‐dimensional uranyl sulfate sheets with a U/S ratio of 2/3. The structural unit of NDUSe is a two‐dimensional uranyl selenate‐selenite sheets with a U/Se ratio of 1/2. In‐situ reaction of the L ‐cystine ligands gives two distinct products for the different acids used here. Where sulfuric acid is used, only H3O+ cations are located in the interlayer space, where they balance the charge of the sheets, whereas where selenic acid is used, interlayer C5H6N+ cations result from the cyclization of the carboxyl groups of L ‐cystine, balancing the charge of the sheets.  相似文献   

5.
Crystal Structure of Potassium Triflate‐butyrolactone, [K3(O3SCF3)3(O2C4H6)2] Single Crystals of [K3(O3SCF3)3(O2C4H6)2] ( 1 ) have been obtained as a by‐product from the reaction of KNPPh3 with Yb(O3SCF3)3 in THF with subsequent addition of butyrolactone. The structure of 1 consists of three symmetry‐independent potassium ions which are linked by the oxygen atoms of the triflate ions and the butyrolactone molecules to give a supramolecular structure with layers normal to the crystallographic b‐axis. The carbonyl oxygen atoms of both butyrolactone molecules show a μ3‐bridging function between three K+ ions, one of them is, in addition, coordinated by the ring O‐atom in a chelate manner. 1 : Space group P21/c, Z = 4, lattice dimensions at 193 K: a = 1155.0(1), b = 1537.2(1), c = 1531.1(1) pm, β = 100.623(7)°, R = 0.0484.  相似文献   

6.
The reaction of Te(OH)6 with Ph3SnOH in ethanol leads to the formation of trans‐[(Ph3SnO)4Te(OH)2] ( 1 ). Compound 1 crystallizes triclinic in the space group P\bar{1} with a = 996.6(2) pm, b = 1365.4(3) pm, c = 1368.2(3) pm and α = 71.15(2)°, β = 71.48(2)°, γ = 74.81(3)° (at 220 K). The molecular structure of 1 consists of a tellurium atom, which is coordinated nearly octahedrally by four Ph3SnO units and two hydroxyl groups that are trans to each other. The Te–O bond lengths are in the range of 190.5(2) and 193.7(2) pm. Treatment of 1 with methanol under reflux yields trans‐[(Ph3SnO)2Te(OMe)4] ( 2 ). Compound 2 crystallizes triclinic in the space group P\bar{1} with a = 1012.8(1) pm, b = 1422.4(2) pm, c = 1618.1(2) pm, and α = 100.44(1)°, β = 107.92(1)°, γ = 110.66(1)° (at 220 K). 2 forms centrosymmetric molecules in which the tellurium atom is surrounded nearly octahedrally by four methoxy groups and two trans arranged Ph3SnO units. The Te–O bond lengths of 187.9(3)–194.5(3) pm are similar to those observed in 1 .  相似文献   

7.
From hydrothermal synthesis needle‐shaped crystals of [Ca3(C6H5O7)2(H2O)2] · 2H2O were obtained. The crystal structure was determined by single‐crystal X‐ray experiments and confirmed by powder data (P$\bar{1}$ (no. 2) a = 5.9466(4), b = 10.2247(8), c = 16.6496(13) Å, α = 72.213(7)°, β = 79.718(7)°, γ = 89.791(6)°, V = 947.06(13) Å3, Z = 2, R1 = 0.0426, wR2 = 0.1037). The structure was obtained from pseudo merohedrically polysynthetic twinned crystals using a combined data collection approach and refinement processes. The observed three‐dimensional network is dominated by eightfold coordinated Ca2+ cations linked by citrate anions and hydrogen bonds between two non‐coordinating crystal water molecules and two coordinating water molecules.  相似文献   

8.
Preparation and Crystal Structures of the first Alkalimetall‐hexacarbonato‐oxotetraberyllates: K6[Be4O(CO3)6] · 7 H2O and K6[Be4O(CO3)6] K6[Be4O(CO3)6] · 7 H2O has been prepared by dissolving freshly precipitated Be(OH)2 in an aqueous KHCO3 solution. After enriching the title compound by extraction with ethanol the heptahydrate crystallizes from the organic phase (triklin, P1¯ (No. 2) with a = 951, 01(11), b = 958, 45(12), c = 1601, 7(2) pm, α = 79, 253(13)°, β = 78, 943(12)°, γ = 65, 119(12)°, VEZ = 1290, 6(3)·106 pm3, Z = 2). Thermal decomposition forms rhombohedral crystals of the anhydrous compound (trigonal‐rhombohedric, R3¯ (No. 148) with a = 1416, 42(6), c = 1704, 5(1) pm, VEZ = 2961, 4(3)·106 pm3, Z = 6).  相似文献   

9.
A new copper(II) phosphonatobenzenesulfonate incorporating 4,4′‐bipyridine (4,4′‐bipy) as auxiliary ligand has been discovered through systematic high‐throughput (HT) screening of the system Cu(NO3)2·3H2O/H2O3PC6H4SO3H/4,4′‐bipy using different solvents. The hydrothermal synthesis of [Cu(HO3PC6H4SO3)(C10H8N2)]·H2O ( 1 ) was further optimized by screening various copper(II) salts. The crystal structure of 1 was determined by single‐crystal X‐ray diffraction and unveiled the presence of isolated sixfold coordinated Jahn–Teller‐distorted Cu2+ ions. The isolated CuN2O4 octahedra are interconnected by phosphonate and sulfonate groups to form chains along the c‐axis. The organic groups, namely phenyl rings and 4,4′‐bipy molecules cross‐link the chains into a three‐dimensional framework. Water molecules are found in the narrow voids in the structure which are held by weak hydrogen bonds. Upon dehydration, the structure of 1 undergoes a phase transition, which was confirmed by TG measurements and temperature dependent X‐ray powder diffraction. The new structure of 1‐h was refined with Rietveld methods. Detailed inspection of the structure revealed the directional switching of the Jahn–Teller distortion upon de/rehydration. Weak ferro‐/ferrimagnetic interactions were observed by magnetic investigations of 1 , which switch to antiferromagnetic below 3.5 K. Compounds 1 and 1‐h are further characterized by thermogravimetric and elemental analysis as well as IR spectroscopy.  相似文献   

10.
Syntheses, crystal structures and thermal behavior of two new hydrated cerium(III) sulfates are reported, Ce2(SO4)3·4H2O ( I ) and β‐Ce2(SO4)3·8H2O ( II ), both forming three‐dimensional networks. Compound I crystallizes in the space group P21/n. There are two non‐equivalent cerium atoms in the structure of I , one nine‐ and one ten‐fold coordinated to oxygen atoms. The cerium polyhedra are edge sharing, forming helically propagating chains, held together by sulfate groups. The structure is compact, all the sulfate groups are edge‐sharing with cerium polyhedra and one third of the oxygen atoms, belonging to sulfate groups, are in the S–Oμ3–Ce2 bonding mode. Compound II constitutes a new structure type among the octahydrated rare‐earth sulfates which belongs to the space group Pn. Each cerium atom is in contact with nine oxygen atoms, these belong to four water molecules, three corner sharing and one edge sharing sulfate groups. The crystal structure is built up by layers of [Ce(H2O)4(SO4)]nn+ held together by doubly edge sharing sulfate groups. The dehydration of II is a three step process, forming Ce2(SO4)3·5H2O, Ce2(SO4)3·4H2O and Ce2(SO4)3, respectively. During the oxidative decomposition of the anhydrous form, Ce2(SO4)3, into the final product CeO2, small amount of CeO(SO4) as an intermediate species was detected.  相似文献   

11.
The crystal of [Co(H2O)6]·(Hnip)2·(H2nip)2·(OMA)2·(H2O)8 has been cultured using direct method and characterized by X-ray single crystal diffractometry, elemental analysis and FTIR spectroscopy. It crystallizes in triclinic system, P-1 space group with the cell parameters of a=0.7012(1) nm, b=1.1378(2) nm, c=1.6612(3) nm, α= 84.92(3)°, β=85.19(3)°, γ=85.91(3)°, V= 1.3128(5) nm^3, Z=1, Dc= 1.573 g·cm^-3. Final R indices [1〉2σ(I)] are: R1 =0.0279, wR2=0.0765 while R indices for all data are: R1 =0.0327, wR2=0.0806. The Co coordination octahadra are each surrounded by two Hnip, two H2nip, two DMA and eight water molecules that are linked by hydrogen bonds and π-π stacking interactions. Thermal analyses of DSC and TG-DTG have been performed on the complex to predict its thermal decomposition mechanism and determine the most probable kinetic model function using Kissinger, Ozawa, integral and differential methods.  相似文献   

12.
The heptacoordinate transition metal coordination compound [Cd(SCZ)3(H2O)](PA)2 · 3H2O ( 1 ) with the ligand semicarbazide (SCZ) and the counteranion picrate (PA) was synthesized and characterized by elemental analysis and FTIR spectroscopy. Single‐crystal X‐ray diffraction analysis revealed that 1 crystallizes in the monoclinic space group P21/c. The Cd2+ ion is heptacoordinated by three SCZ groups and a water molecule. SCZ presents typical bidentate coordination modes. The thermal decomposition mechanism of 1 was studied by differential scanning calorimetry (DSC), which revealed that complex 1 exhibits three small endothermic and two large exothermic processes. The non‐isothermal kinetics parameters were calculated by the Kissinger's method and Ozawa‐Doyle's method, respectively. The heat of combustion was measured by oxygen bomb calorimetry. The enthalpy of formation, the critical temperature of thermal explosion, the entropy of activation (ΔS), the enthalpy of activation (ΔH), and the free energy of activation (ΔG) were also calculated. Sensitivity tests revealed that 1 is insensitive to mechanical stimuli.  相似文献   

13.
Dicarboxylate Groups as Ligands and Anions in Aquamagnesium Complexes: Crystal Structures of [Mg (C4H2O4)(H2O)4] · H2O and [Mg(H2O)6](C4HO4)2 · 2H2O ((C4H2O4)2— = Fumarate; (C4HO4) = Hydrogenacetylenedicarboxylate) Crystals of tetraaqua(fumarato)magnesium‐hydrate ( 1 ) and hexaaquamagnesium‐bis(hydrogenacetylenedicarboxylate)‐dihydrate ( 2 ) were prepared by reacting MgCl2 with sodium fumarate and acetylenedicarboxylic acid, respectively. In 1 cis‐Mg(H2O)4 units are bridged by α, Ö‐bonded fumarate groups. The resulting zig zag chains exhibit the maximum symmetry compatible with space group symmetry C2/c. 2 consists of layers of voluminous [Mg(H2O)6]2+ cations alternating with layers of C4HO4 anions. The nearly planar anions are held together by parallel stacking and by short hydrogen bonds. Both structures contain efficient H bridging systems. 1 : Space group C2/c, Z = 4, lattice constants at 20 °C: a = 5.298(1), b = 13.178(2), c = 13.374(2)Å; ß = 94.79(2)°, R1 = 0.024. 2 : Space group P1, Z = 1, lattice constants at 20 °C: a = 5.985(1), b = 6.515(1), c = 11.129(1)Å; α = 105.24(2), ß = 91.87(3), γ = 90.92(1)°, R1 = 0.034.  相似文献   

14.
15.
Yellow crystals of Bi(SCN)3·1/2H2O are obtained by reacting (BiO)2CO3 and HSCN in aqueous solution. X‐ray diffraction on a single‐crystal revealed a triclinic lattice (space group P ) with a = 843.6(2) pm, b = 920.4 (2) pm, c = 1210.7(2) pm, α = 109.16(3) °, β = 109.06(3) °, γ = 90.22(3) °, V = 832.8(3)·106 pm3, and Z = 4. All thiocyanate anions bind with both ends to different cations. The coordination network expands in plane layers parallel (1 0). The water molecule coordinates one of the two independent Bi3+ cations. Dehydration sets in at 100 °C, followed by stepwise thermal decomposition to Bi2S3.  相似文献   

16.
Crystal Structure of Sr(BrO3)2 · H2O, Ba(BrO3)2 · H2O, Ba(IO3)2 · H2O, Pb(ClO3)2 · H2O, and Pb(BrO3)2 · H2O The crystall structures of the isostructural halates Sr(BrO3)2 · H2O, Ba(BrO3)2 · H2O, Ba(IO3)2 · H2O, Pb(ClO3)2 · H2O, and Pb(BrO3)2 · H2O were determined using X-ray single crystal data (monoclinic space group C2/c? C, Z = 4), The mean bond lengths and bond angles of the halate ions in the Ba(ClO3)2 · 1 H2O-type compounds, which correspond to those of other halates, are Cl? O, 149.0, Br? O, 165.9, I? O, 180.2 pm, ClO3?, 106.4, BrO3?, 104.0, and IO3?, 99.6°. The structure data obtained are discussed in terms of possible orientational disorder of the water molecules, strengths of the hydrogen bonds, influence of the lead ions on the structure, and site group distortion of the halate ions.  相似文献   

17.
In the course of investigations relating to magnesia oxysulfate cement the basic magnesium salt hydrate 3Mg(OH)2 · MgSO4 · 8H2O (3–1–8 phase) was found as a metastable phase in the system Mg(OH)2‐MgSO4‐H2O at room temperature (the 5–1–2 phase is the stable phase) and was characterized by thermal analysis, Raman spectroscopy, and X‐ray powder diffraction. The complex crystal structure of the 3–1–8 phase was determined from high resolution laboratory X‐ray powder diffraction data [space group C2/c, Z = 4, a = 7.8956(1) Å, b = 9.8302(2) Å, c = 20.1769(2) Å, β = 96.2147(16)°, and V = 1556.84(4) Å3]. In the crystal structure of the 3–1–8 phase, parallel double chains of edge‐linked distorted Mg(OH2)2(OH)4 octahedra run along [–110] and [110] direction forming a pattern of crossed rods. Isolated SO4 tetrahedra and interstitial water molecules separate the stacks of parallel double chains.  相似文献   

18.
Single crystals of [Be33‐O)3(MeCN)6{Be(MeCN)3}3](I)6·4CH3CN ( 1 ·4CH3CN) were obtained in low yield by the reaction of beryllium powder with iodine in acetonitrile suspension, which probably result from traces of beryllium oxide containing the applied beryllium metal. The compound 1 ·4CH3CN forms moisture sensitive, colourless crystal needles, which were characterized by IR spectroscopy and X‐ray diffraction (Space group Pnma, Z = 4, lattice dimensions at 100(2) K: a = 2317.4(1), b = 2491.4(1), c = 1190.6(1) pm, R1 = 0.0315). The hexaiodide complex cation 1 6+consists of a cyclo‐Be3O3 core with slightly distorted chair conformation, stabilized by coordination of two acetonitrile ligands at each of the beryllium atoms and by a {Be(CH3CN)3}2+ cation at each of the oxygen atoms. This unique coordination behaviour results in coplanar OBe3 units with short Be–O distances of 155.0 pm and 153.6 pm on average of bond lengths within the cyclo‐Be3O3 unit and of the peripheric BeO bonds, respectively. Exposure of compound 1 ·4CH3CN to moist air leads to small orange crystal plates of [Be(H2O)4]I2·2CH3CN ( 3 ·2CH3CN). According to the crystal structure determination (Space group C2/c, Z = 4, lattice dimensions at 100(2) K: a = 1220.7(1), b = 735.0(1), c = 1608.5(1) pm, β = 97.97(1)°, R1 = 0.0394), all hydrogen atoms of the dication [Be(H2O)4]2+ are involved to form O–H ··· N and O–H ··· I hydrogen bonds with the acetonitrile molecules and the iodide ions, respectively. Quantum chemical calculations (B3LYP/6‐311+G**) at the model [Be33‐O)3(HCN)6{Be(HCN)3}3]6+ show that chair and boat conformation are stable and that the distorted chair conformation is stabilized by packing effects.  相似文献   

19.
The syntheses of the antimony analogue of betaine, Me3Sb+CH2COO? (1), of the precursor [Me3SbCH2COOH][Br] (2) and of [Me3SbCH2COOCH2CH3][Br] (3) are reported. A new method for the synthesis of solvent‐free Me3Sb is described. The structures of 1·H2O and 3 were determined by single crystal X‐ray diffractometry. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

20.
Alkaline Molybdotellurates: Preparation and Crystal Structures of Rb6[TeMo6O24] · 10H2O and Rb6[TeMo6O24] · Te(OH)6 · 6H2O Single crystals of Rb6[TeMo6O24] · 10 H2O and Rb6[TeMo6O24] · Te(OH)6 · 6 H2O, respectively, were grown from aqueous solution. Rb6[TeMo6O24] · 10 H2O possesses the space group P1 . The lattice dimensions are a = 963.40(13), b = 972.56(12), c = 1 056.18(13) pm, α = 97.556(10), β = 113.445(9), γ = 102.075(10)°; Z = 1, 2 860 reflections, 215 parameters refined, Rg = 0.0257. The centrosymmetrical [TeMo6O24]6? anions are stacked parallel to [010]. Rb(2) is coordinated with one exception by water molecules only. Folded chains consisting of [TeMo6O24]6? anions and Rb(2) coordination polyhedra which are linked to pairs represent the prominent structural feature. Rb6[TeMo6O24] · Te(OH)6 · 6 H2O crystallizes monoclinically in the space group C2/c with a = 1 886.4(3), b = 1 000.9(1), c = 2 126.5(3) pm, and β = 115.90(1)°; Z = 4, 3 206 reflections, 240 parameters refined, Rg = 0.0333. It is isostructural in high extent with (NH4)6[TeMo6O24] · Te(OH)6 · 7 H2O. Hydrogen bonds between Te(OH)6 molecules and [TeMo6O24]6? anions establish infinite strands. The [TeMo6O24]6? anions gather around Te(OH)6 providing channel-like voids extending parallel to [001].  相似文献   

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