(NH4)4P4O12 · 2Te(OH)6 · 2H2O,the first example of a tetrametaphosphate-tellurate

Ammonium tetrametaphosphate-tellurate dihydrate, (NH₄)₄P₄O₁₂ · 2Te(OH)₆ · 2H₂O, is triclinic with the following unit cell dimensions: a = 11.845(6), b = 8.554(5), c = 7.433(5) Å, α = 66.28(5), β = 95.91(5), γ = 76.00(5)° space group: $\text{P}\text{1}$ and Z = 1. The crystal structure has been determined with a final R value of 0.021. As in the previously described phosphate-tellurates, monophosphate-tellurate and trimetaphosphate-tellurates, the phosphoric anion (here the P₄O₁₂ ring) is independent of the octahedral Te(OH)₆ group. A complete pattern of the hydrogen bonds is given.     

Synthesis and structure of tetrakis(phenylenethiourea)tellurium(II) chloride dihydrochloride,C28H26N8S4Cl4Te

Reaction of tellurium(IV) with excess phenylenethiourea(2-mercaptobenzimidazole) in aqueous methanolic hydrochloric acid leads to the formation of Te(II) complex, tetrakis(phenylenethiourea)tellurium(II) chloride dihydrochloride. The characterisation and crystal structure of the complex are reported. The crystals are monoclinic, space group P2₁/c, a = 13.939(5), b = 26.523(9), c = 4.873(2) Å, β = 100.29(4)°, V = 1772.6 ų, M = 872.4, D_c = 1.651 g cm^?3, Z = 2, F(000) = 868, μ(MoK_α) = 1.298 mm^?1. Final R = 0.055 and R_W = 0.056 for 918 independent reflections. The tellurium atom in the molecule lies at the crystallographic centre of symmetry and is bonded to four phenylenethiourea sulphur atoms in a square planar arrangement with TeS(1) = 2.678(6), TeS(2) = 2.674(5) Å and S(1)TeS(2) is 90.5(3)°. The ligand behaves as a thione. Chlorine atoms remain outside the coordination sphere of the Te and stabilise the packing arrangement in the unit cell through hydrogen bondings to nitrogen atoms.     

Darstellung und eigenschaften von octafluorbutansulfonsäure H(CF2)4SO3H und einigen ihrer derivate

Perfluorobutanesulfonyl fluoride C₄F₉SO₂F, obtained by electrofluorination of sulfolene, may contain up to 10 % of perfluorotetramethylene sulfone. Upon hydrolysis with base, this sulfone yields octafluorobutanesulfonate ion H(CF₂)₄SO^ø₃ (V). Perfluorobutanesulfonic acid and octafluorobutanesulfonic acid (VI) which are readily obtained from the salts and H₂SO₄ can be separated via fractional distillation. VI forms a crystalline monohydrate, M.P. 45°C. The trimethylsilyl ester was obtained from VI and (CH₃)₃ SiCl. Upon heating above 250° the K sulfonate (Vb) liberates HF.     

Structural, vibrational and dielectric properties of the new mixed solution K0.84(NH4)1.16SO4Te(OH)6

Synthesis, crystal structure, DSC characterization, dielectric and Raman measurements are given for a new mixed solution K_0.84(NH₄)_1.16SO₄Te(OH)₆ (KNST). X-ray studies showed that the title compound crystallizes in the monoclinic system (P2₁/c) with the following parameters: , , , β=120.17(2)° and Z=4. The structure can be regarded as being built of isolated TeO₆ octahedra, SO₄ tetrahedra and cations. The main feature of this structure is the coexistence of two types of hydrogen bonds OHO and NHO ensuring the cohesion of the crystal. Crystals of K_0.84(NH₄)_1.16SO₄Te(OH)₆ undergo two endothermic peaks at 425 and 480 K and a shoulder at 470 K. These transitions detected by DSC and analyzed by dielectric measurements using the impedance and modulus spectroscopy techniques. Raman scattering measurements on K_0.84(NH₄)_1.16SO₄Te(OH)₆ material taken between 300 and 620 K are reported in this paper. The spectra indicate clearly two phase transitions.     

Syntheses and structural studies on two cycloruthenapentadienyl complexes: [(CO)3RuC4(CH2OH)4]Ru(CO)3·H2O and [(CO)3RuC4(CH2CH2OH)2(C2H5)2]Ru(CO)3

Syntheses and single-crystal X-ray diffraction studies have been completed on two cycloruthenapentadienyl (CO)₆Ru₂L₂ derivatives, with L = CH₂OHC = CCH₂OH and C₂H₅C=CCH₂CH₂OH respectively. Crystal data are as follows: for [(CO)₃RuC₄(CH₂OH)₄]Ru(CO)₃·H₂O, P2₁/c, a 13.72(1), b 9.501(4), c 14.86(1) Å, β 101.10(6)°, R_w = 0.052 for 1911 reflections; for [(CO)₃RuC₄(CH₂CH₂OH)₂(C₂H₅)₂]Ru(CO)₃, P2₁/c, a 9.191(3), b 16.732(4), c 14.903(3) Å, β 113.61(4)°, R_w = 0.042 for 2865 reflections. Both compounds are built up from binuclear units, each unit being regarded as a Ru(CO)₃ fragment π-bonded to a cycloruthenapentadienyl ring. The molecular parameters are compared with those of known cyclometallapentadienyl complexes of transition metals. The presence of a semi-bridging CO group is discussed.     

On basic thallium sulfates: Structure of Tl2Tl OH(SO4)2

The Tl₂TlOH(SO₄)₂ compound is monoclinic, a = 7.758 (3), b = 17.587 (9), c = 7.356 (3) Å, β = 119.91 (3)°, S. G. Cc, Z = 4. The structure was solved by full-matrix least square refinement to R = 0.033 from 1242 single-crystal reflections collected on an automated diffractometer. Tl⁺ ions ensure bonding between [Tl^IIIOH(SO₄)₂]_∞ sheets. These sheets may be viewed as criss-crossing TlSO₄ chains. In the [101] direction, the linking of Tl^III is reinforced by bidentate OH groups, so the usual hexacoordination of trivalent thallium is preserved. A transition occurring at 104°C is under investigation.     

Thermal behaviour of two new salts of malonic acid: Cu(C3H2O4)·4H2O and Cu(NH4)2(C3H2O4)2

Two new salts of malonic acid have been prepared: the copper(II) malonate tetrahydrate and the copper(II)-ammonium double malonate. Their study by thermal analysis (TG and DTA) leads to the following results:Cu(C₃H₂O₄)·4H₂O: the dehydration is rather complex and it is only under careful conditions that an intermediate hydrate Cu(C₃H₂O₄)·3H₂O could be traced. At about 170°C the dehydration is not ended (the salt holds yet about 0.15H₂O) and the anhydrous salt occurs only at about 240°C. It decomposes immediately leading to residues the composition of which depends upon the surrounding atmosphere; the part played by the gas given off is discussed.Cu(NH₄)₂(C₃H₂O₄)₂: this salt melts and decomposes simultaneously at about 190°C. During the decomposition the copper nitride Cu₃N forms as intermediate compound (as well as copper metal). Concerning the final residues of the decomposition the results and the conclusions are the same as the ones of the previous case.     

Thermal analysis of β-Co2(OH)3Cl and Zn5(OH)5Cl2 · H2O

Samples of β-Co₂(OH)₃Cl and Zn₅(OH)₈Cl₂ · H₂O have been prepared and their thermal decomposition studied in air and N₂ by DTA and TG up to 1000°C. X-Ray diffraction analysis of the thermal treatment products in air at various temperatures from 100 to 100°C was also carried out. The results obtained made it possible to establish the steps through which the pyrolysis of both compounds proceeds.     

Eu(C10H9N2O4)(C10H8N2O4)(H2O)3]•0.5bipy•3H2O配合物的合成、晶体结构及荧光性质

在水-乙醇混合体系中, 以2-羰基丙酸水杨酰腙(C₁₀H₁₀N₂O₄)、2,2-联吡啶(C₁₀H₈N₂, 简写bipy)与Eu(NO₃)₃•4H₂O反应, 首次培养出黄色单晶[Eu(C₁₀H₉N₂O₄)(C₁₀H₈N₂O₄)(H₂O)₃]•0.5bipy•3H₂O. 该晶体属三斜晶系, 空间群为P-1, 晶胞参数a＝0.93392(16) nm, b＝1.3100(2) nm, c＝1.3895(2) nm, α＝97.205(3)°, β＝105.411(2)°, γ＝106.364(2)°, V＝15.35(2) nm³, Z＝2, μ＝2.118 mm^－1, D_c＝1.686 Mg/m³, F(000)＝786, R＝0.0116, wR＝0.0507, GOF＝0.995. 晶体测试结果表明, 该单晶结构为铕的9配位配合物, 两个2-羰基丙酸水杨酰腙分别以负一价和负二价酮式和三个水分子同时参与配位; 每个2-羰基丙酸水杨酰腙中的羧基氧、酰胺基中的羰基氧和C＝N中的氮与Eu^3＋配位, 形成两个共边的稳定五元环, 另三个配位原子则分别来自三个水分子中的氧原子, 该配合物在空间呈扭曲的单帽四方反棱柱, 而在不对称单位中还有游离的一个2,2-联吡啶分子和三个水分子, 这些游离分子与配位分子之间存在大量分子内和分子间氢键, 整个分子在空间呈三维网状结构. 发光性能测试表明该配合物具有很好的荧光性质.     

Phase equilibrium relations in the binary systems LiPO3CeP3O9 and NaPO3CeP3O9

The LiPO₃CeP₃O₉ and NaPO₃CeP₃O₉ systems have been investigated for the first time by DTA, X-ray diffraction, and infrared spectroscopy. Each system forms a single 1:1 compound. LiCe(PO₃)₄ melts in a peritectic reaction at 980°C. NaCe(PO₃)₄ melts incongruently, too, at 865°C. These compounds have a monoclinic unit cell with the parameters: a = 16.415(6), b = 7,042(6), c = 9.772(7)Å; β = 126.03(5)°; Z = 4; space group $\text{C}{}_2\text{c}$ for LiCe (PO₃)₄; and a = 9.981(4), b = 13.129(6), c = 7.226(5) Å, β = 89.93(4)°, Z = 4, space group $\text{P2}{}_1\text{n}$ for NaCe(PO₃)₄. It is established that both compounds are mixed polyphosphates with chain structure of the type |M^I_IM^III_II (PO₃)₄|_∞M^I_I: alkali metal, M^III_II: rare earth.     

A new ferroelastic transition in some A2(MO4)3 molybdates and tungstates

We have found for the first time a ferroelastic transition in many molybdates and tungstates with the Sc₂(MoO₄)₃-type structure. Below the transition these phases are monoclinic ($\text{P2}{}_1\text{a}$), and above the transition they are orthorhombic (Pnca). Observed transition temperatures are: Al₂(MoO₄)₃, 200°C; Al₂(WO₄)₃, ?6°C; Cr₂(MoO₄)₃, 385°C; Fe₂(MoO₄)₃, 499°C; In₂(MoO₄)₃, 335°C; In₂(WO₄)₃, 252°C; and Sc₂(MoO₄)₃, 9°C.     

New versatile organyltellurium(IV) halides: Synthesis and X-ray structural features of the telluronium tellurolate salts [PhTe(CH3)2]2[TeX6] (X = Cl, Br) and [Ph3Te][PhTeX4] (X = Cl, Br, I)

TeX₄ (X = Cl, Br) react in HCl/HBr with [Ph(CH₃)₂Te]X (X = Cl, Br) to give [PhTe(CH₃)₂]₂[TeCl₆] (1) and [PhTe(CH₃)₂]₂[TeBr₆] (2). The reaction of PhTeX₃ (X = Cl, Br, I) in cooled methanol with [(Ph)₃Te]X (X = Cl, Br, I) leads to [Ph₃Te][PhTeCl₄] (3), [Ph₃Te][PhTeBr₄] (4) and [Ph₃Te][PhTeI₄] (5). In the lattices of the telluronium tellurolate salts 1 and 2, octahedral TeCl₆ and TeBr₆ dianions are linked by telluronium cations through Te?Cl and Te?Br secondary bonds, attaining bidimensional (1) and three-dimensional (2) assemblies. The complexes 3, 4 and 5 show two kinds of Te?halogen secondary interactions: the anion-anion interactions, which form centrosymmetric dimers, and two identical sets of three telluronium-tellurolate interactions, which accomplish the centrosymmetric fundamental moiety of the supramolecular arrays of the three compounds, with the tellurium atoms attaining distorted octahedral geometries. Also phenyl C-H?halogen secondary interactions are structure forming forces in the crystalline structures of compounds 3, 4 and 5.     

A dipole moment study of the conformational properties of diaryl diselenides and related compounds

The electric dipole moments of the diaryl diselenides (RC₆H₄)₂Se₂ (R  H, 4-F, 4-Br, 4-CH₃, 3-F) were measured in benzene solution at 25 and 45°C. The conformations of these compounds were deduced by matching experimental moments with values calculated for a variety of possible conformations. In the dissolved state the diselenides exist at 25°C in fixed “skew” conformations characterized by dihedral angles of 75–106° between the CSeSe planes, corresponding to the conformational energy minima. At 45°C oscillations about the SeSe bonds are excited in the diphenyl and bis(4-methylphenyl) diselenides, whereas the 4-bromophenyl derivative exhibits free rotation. The fluoro compounds have temperature-independent dipole moments, suggesting “rigid conformations” with dihedral angles of 106° (4-F) and 74.4° (3-F). An analysis of the dipole moments at 25 and 45°C obtained for the compounds (RC₆H₄)₂X₂ (R  H, 3-F, 4-F, 4-Br, 4-CH₃; X  S, Se, Te) showed that the conformational properties of these derivatives change on passing from X  S to X  Te. The observed variations are explicable in terms of a decreasing repulsion between the lone electron pairs of the chalcogen atoms on going from the disulfides to the ditellurides and a concomitant reduction of the energy barrier to rotations about the XX bonds.     

Synthesis and complexation of a new facultative tridentate S2Te donor ligand MeS(CH2)3Te(CH2)3SMe: crystal structures of [Rh(Cp*)(S2Te)][PF6]2 and [PtCl(S2Te)]PF6

The syntheses and spectroscopic characterisation of the new facultative tridentate tellurium containing ligands MeS(CH₂)₃Te(CH₂)₃SMe (S₂Te) and H₂N(CH₂)₃Te(CH₂)₃NH₂ are described. The complexes of the former, fac-[Mn(CO)₃(S₂Te)]CF₃SO₃, [Rh(Cp*)(S₂Te)][PF₆]₂, [MCl(S₂Te)]PF₆ (M=Pd or Pt), [Cu(S₂Te)]BF₄ and [Ag(S₂Te)]CF₃SO₃ have been prepared and characterised by analysis, IR, ¹H-, ¹³C{¹H}-, ¹²⁵Te- and ¹⁹⁵Pt-NMR spectroscopy and mass spectrometry. The X-ray crystal structures of [Rh(Cp*)(S₂Te)][PF₆]₂ and [PtCl(S₂Te)]PF₆ are described. The results are compared with those obtained from complexes of the related tridentates Te{(CH₂)₃TeR}₂, Se{(CH₂)₃SeMe}₂ and S{(CH₂)₃SR}₂.     

Chromium(III) Hydroxide Solubility in the Aqueous K+-H+-OH?-CO2-HCO 3? -CO 32? -H2O System: A?Thermodynamic Model

Chromium(III)-carbonate reactions are expected to be important in managing high-level radioactive wastes. Extensive studies on the solubility of amorphous Cr(III) hydroxide solid in a wide range of pH (3–13) at two different fixed partial pressures of CO₂(g) (0.003 or 0.03 atm.), and as functions of K₂CO₃ concentrations (0.01 to 5.8 mol⋅kg⁻¹) in the presence of 0.01 mol⋅dm⁻³ KOH and KHCO₃ concentrations (0.001 to 0.826 mol⋅kg⁻¹) at room temperature (22±2 °C) were carried out to obtain reliable thermodynamic data for important Cr(III)-carbonate reactions. A combination of techniques (XRD, XANES, EXAFS, UV-Vis-NIR spectroscopy, thermodynamic analyses of solubility data, and quantum mechanical calculations) was used to characterize the solid and aqueous species. The Pitzer ion-interaction approach was used to interpret the solubility data. Only two aqueous species [Cr(OH)(CO₃)₂²⁻ and Cr(OH)₄CO₃³⁻] are required to explain Cr(III)-carbonate reactions in a wide range of pH, CO₂(g) partial pressures, and bicarbonate and carbonate concentrations. Calculations based on density functional theory support the existence of these species. The log ₁₀ K° values of reactions involving these species [{Cr(OH)₃(am) + 2CO₂(g)⇌Cr(OH)(CO₃)₂²⁻+2H⁺} and {Cr(OH)₃(am) + OH⁻+CO₃²⁻ ⇌Cr(OH)₄CO₃³⁻}] were found to be −(19.07±0.41) and −(4.19±0.19), respectively. No other data on any Cr(III)-carbonato complexes are available for comparisons.     

Heat capacity and thermodynamic functions of MnBr2 · 4D2O and MnCl2 · 4D2O

The heat capacities of MnBr₂ · 4D₂O and MnCl₂ · 4D₂O have been experimentally determined from 1.4 to 300 K. The smoothed heat capacity and thermodynamic functions (H°_TH°₀) and S°_T are reported for the two compounds over the temperature range 10 to 300 K. The error in the thermodynamic functions at 10 K is estimated to be 3%. Additional error in the tabulated values arising from the heat capacity data above 10 K is thought to be less than 1%. A λ-shaped heat capacity anomaly was observed for MnCl₂ · 4D₂O at 48 K. The entropy associated with the anomaly is 1.2 ± 0.2 J/mole K.     

Preparation of high-purity titanium salts from the system (NH4)2TiF6-(NH4)3FeF6-NH4F-H2O

Influence of NH₄F concentration on the conditions of separation of Ti(IV) and Fe(III) salts by fractional hydrolysis under the action of ammonia in the system (NH₄)₂TiF₆-(NH₄)₃FeF₆-NH₄F-H₂O was studied. The coprecipitation of (NH₄)₃TiO₂F₅ and (NH₄)₃FeF₆ as a result of crystallochemical substitution of Fe⁺³ for Ti⁺⁴ makes it possible to reduce the content of Fe(III) salts in the system. After separation of a precipitate containing up to 25% of Ti from solutions with NH₄F concentrations from 10.6 to 22.3% and subsequent hydrolysis, the remaining titanium precipitates. The precipitate is annealed up to 800°C in the presence of water vapor to form TiO₂ with a whiteness above 92%. Original Russian Text ? N.G. Bakeeva, P.S. Gordienko, E.V. Pashnina, 2009, published in Zhurnal Obshchei Khimii, 2009, Vol. 79, No. 1, pp. 3–8.     

Crystal and molecular structure of tricyclopentadienyltetrahydrofuranuranium(III), (η5-C5H5)3U·OC4H8

Tricyclopentadienyltetrahydrofuranuranium(III), (η⁵-C₅H₅)₃U·OC₄H₈, crystallizes in the centrosymmetric monoclinic space group P2₁/n with a 8.248(3), b 24.322(17), c 8.357(4) Å, β 101.29(5)°, V 1644.0 ų and ρ(calc) 2.04 g cm^?1 for Z = 4 and mol.wt. 595.0. Diffraction data (Mo-K_α, 2θ(max) 45°) were collected on an Enraf-Nonius CAD4 diffractometer and the structure was refined to R_w(F) 4.7% for those 1530 reflections having I > 2σ(I). The molecule consists of a distorted tetrahedral arrangement of THF and (η⁵-C₅H₅) ligands with CpUCp angles in the range 110.4–122.4° and CpUO angles between 90.2 and 106.0°. Individual uranium-carbon distances range from 2.76(2) to 2.82(2) Å and average 2.79[1] Å. The uranium-oxygen distance of 2.551(10) Å suggests a 10-coordinate U³⁺ radius of 1.20 Å in this class of compounds.     

Crystal and molecular structure of (NH4)2[UO2(NO3)4] and [(NH4)(18C6)]2[UO2(NO3)4]

Single crystals of diammonium tetranitratouranylate (NH₄)₂[UO₂(NO₃)₄] (I) and a new diammonium tetranitratouranylate complex with 18-crown-6 [(NH₄)(18C6)]₂[UO₂(NO₃)₄] (II) have been synthesized by the reaction of diaquadinitratouranyl tetrahydrate with ammonium nitrate in a nitric acid solution and the reaction of the same reagents with 18C6 in an ethanol solution, respectively. The X-ray diffraction analysis of compounds I and II has been performed. Crystals of compounds I and II are monoclinic, Z = 2, space group P2₁/n, a = 6.4075(5) ?, b = 7.7851(7) ?, c = 12.4461(12) ?, β = 101.239(1)°, V = 608. 94(9) ?³ for compound I and a = 10.542(9) ?, b = 8.590(8) ?, c = 22.5019(19) ?, β = 101.632(1)°, V = 2058.3(3) ?³ for compound II. The [UO₂(NO₃)₄]²⁻ complex anion in compounds I and II contains two monodentate and two bidentate cyclic nitrato groups, and the coordination number of uranyl is 6. The 18C6 molecule in the structure of compound II has the classic crown conformation and combined with the ammonium ion by three hydrogen bonds. Compounds I and II formed by electrostatic attraction forces between counterions are stabilized by (NH₄⁺)NH...O(NO₃⁻) interionic hydrogen bonds.     

The crystal and molecular structure of 3,4-quinoxalino-1-telluracyclopentane C10H8N2TeII

The crystal and molecular structure of 3,4-quinoxalino-1-tellura(II)cyclopentane has been determined by X-ray diffraction at room temperature. The crystals are tetragonal, space group I4₁/a with a = b = 25.315(8), c = 6.010(1) Å and V = 3851.38 ų. The density of 1.96 g cm^?3 calculated on the basis of 16 molecules per unit cell is in agreement with the flotation value of 1.91 g cm^?3. The structure has been refined to a conventional R value of 0.0408 using 744 independent observed reflections obtained from four-circle diffractometer measurements. The structure consists of discrete molecules TeC = 2.134 Å (av.), CN = 1.343 Å (av.) and angle CTeC = 80.7° (e.s.d. 0.5) but the intermolecular TeTe bonds (3.791 and 3.998 Å) are less than the sum of the Van der Waals' radii thus indicating the presence of secondary bonding. These short intermolecular contacts in the crystal structure are consistent with the anomalous physical properties observed.