Phase formation upon crystallization of SrO · 2B<Subscript>2</Subscript>O<Subscript>3</Subscript> glasses

The crystallization of SrO · 2B₂O₃ glasses has been studied. Four different crystalline formations were found to form simultaneously and independently on the glass surface: stable α-SrB₄O₇ crystals and metastable crystalline forms (β-SrB₄O₇, Sr₄B₁₄O₂₅, and spherulites (presumably, mixtures of crystalline phases)). The ranges of thermal stability of the newly formed metastable phases have been established using thermal analysis.     

Synthesis and Crystal Structure of the Heteronuclear Decavanadates Complex: [Fe(phen)<Subscript>3</Subscript>]<Subscript>2</Subscript>·[V<Subscript>10</Subscript>O<Subscript>28</Subscript>]·15H<Subscript>2</Subscript>O

Abstract  

A new decavanadate metal complex [Fe(phen)₃]₂·[V₁₀O₂₈]·15H₂O (phen = 1,10-phenanthroline) has been synthesized from a hydrothermal reaction and the crystal structure has been determined by means of single-crystal X-ray diffraction. The crystal structure analysis reveals that the polyoxoanions are decorated with the [Fe(phen)₃]³⁺ cations, and that the water molecules play the bridge role on the packing modes. They are further contacted to form supramolecular networks through extensive hydrogen bonding.     

Crystal structure of Sr(AsUO<Superscript>6</Superscript>)<Subscript>2</Subscript> · 8H<Subscript>2</Subscript>O

The crystal structure of the compound Sr(AsUO₆)₂ · 8H₂O is determined by X-ray diffraction analysis (monoclinic system, sp. gr. Pc, unit-cell parameters a = 7.154(1) Å, b = 7.101(1) Å, c = 18.901(7) Å, β = 92.67(2)°, Z = 2). The structure is built by (001)-parallel [AsUO₆]^? layers formed by flattened square UO₆ bipyramids and AsO₄ tetrahedra. The neighboring layers are connected via SrO₈ square antiprisms. The cavities of the polyhedral framework thus formed are occupied by H₂O molecules. The displacements of the anion complexes by a half-translation with respect to one another along only one lattice period is a characteristic feature of this polymorphous modification of the uran-mica group.     

Pseudosymmetry in Cr(urea)<Subscript>4</Subscript>(H<Subscript>2</Subscript>O)<Subscript>2</Subscript>·3NO<Subscript>3</Subscript>

Abstract  

The low temperature crystal structure of the complex, Cr(urea)₄(H₂O)₂·3NO₃ (1), displays intriguing pseudosymmetry that complicates the structure determination. 1 crystallises in the centrosymmetric monoclinic space group P2₁/c with Z = 8 and Z′ = 2; a = 18.3338(4) ?, b = 16.5472(4) ?, c = 13.9252(3) ? and β = 106.3260(10)°, V = 4054.19(16) ?³. The two symmetry independent [Cr(urea)₄(H₂O)₂]³⁺ ions in the asymmetric unit both feature coordinated urea (O=C(NH₂)₂) and lie on general positions. A further six independent nitrate anions complete the structure. The unit cell is primitive but the two Cr³⁺ ions are related by a pseudo translation of ?, ?, 0. The deviation from a truly C-centred cell is clear from an examination of geometry of the urea ligands and the hydrogen bonds which they form. The identification of the space group in this case is described and methods for quantifying the degree of deviation from a C-centred cell discussed.     

Crystal structure of the solid solution NH<Subscript>4</Subscript>Al<Subscript>0.62</Subscript>Cr<Subscript>0.38</Subscript>(SO<Subscript>4</Subscript>)<Subscript>2</Subscript> · 12H<Subscript>2</Subscript>O

The solid solution NH₄Al_0.62Cr_0.38(SO₄)₂ · 12H₂O was studied by X-ray diffraction. The crystal structure was determined in a series of the maximal subgroups Pa3? > R3? > P1? > P1. Reflections forbidden in sp. gr. Pa3? are indicative of symmetry lower than cubic. In the centrosymmetric models under consideration, all sulfate groups are oppositely oriented with respect to each other. In non-centrosymmetric sp. gr. P1, four of the eight sulfate groups have the same orientation, whereas the other four groups are oriented in an opposite direction.     

Crystal structure of CoUO<Subscript>2</Subscript>(SO<Subscript>4</Subscript>)<Subscript>2</Subscript> · 5H<Subscript>2</Subscript>O at 293 K

Single crystals of cobalt uranyl sulfate are grown. The crystal structure is established by X-ray diffraction: the orthorhombic system, sp. gr. Pmc2₁, a = 6.452(2) Å, b = 8.295(2) Å, c = 11.288(3) Å, R₁ = 0.0303, wR₂ = 0.0735 for reflections with I > 2σ(I). The structure of CoUO₂(SO₄)₂ · 5H₂O consists of infinite two-dimensional uncharged [CoUO₂(SO₄)₂H₂O]_2∞ layers, which are linked to each other by hydrogen bonds.     

Crystal and molecular structure of phenanthrolinium peroxodisulfate dihydrate (C<Subscript>12</Subscript>H<Subscript>9</Subscript>N<Subscript>2</Subscript>)<Subscript>2</Subscript>S<Subscript>2</Subscript>O<Subscript>8</Subscript> · 2H<Subscript>2</Subscript>O

The crystal structure of (HPhen)₂S₂O₈ · 2H₂O is studied using X-ray diffraction. The crystals are monoclinic, a = 23.716(5) Å, b = 10.220(2) Å, c = 13.103(3) Å, β = 128.03(2)°, V = 2501.6(9) ų, Z = 4, space group C2/c, and R = 0.0745 for 1579 reflections with I > 2σ(I). The crystal is built of S₂O ₈ ^2? centrosymmetric anions, HPhen ⁺ cations, and molecules of crystallization water. Hydrogen bonds link the structural units into chains. Within a chain, stacking interactions are observed between the phenanthroline rings (the interplanar spacing between the rings is 3.8 Å, and the dihedral angle between their planes is 8°). The data of IR spectroscopy confirm the formation of the N(Phen)-H bond.     

Solvothermal Syntheses and Crystal Structures of Rare Earth Thioantimonates [Y(en)<Subscript>4</Subscript>]SbS<Subscript>4</Subscript>·0.5en and [Tm(en)<Subscript>4</Subscript>]SbS<Subscript>4</Subscript>·0.5en

Abstract  

Two rare earth metal thioantimonates [RE(en)₄]SbS₄·0.5en (RE = Y(1), Tm(2); en = ethylenediamine) were synthesized under mild solvothermal conditions. Compounds 1 and 2 are isostructural, and both crystallize in monoclinic space group P2₁/n. Crystallographic data for 1: a = 11.0894(19), b = 12.905(2), c = 16.000(3) ?, β = 91.792(4), V = 2288.7(7) ?³, Z = 4. For 2: a = 11.0870(14), b = 12.8977(16), c = 15.986(2) ?, β = 91.879(3), V = 2284.7(5) ?³, Z = 4. The four-en coordinated rare earth complex cation [RE(en)₄]³⁺ formed in situ balances the charge of the [SbS₄]³⁻ anion in the crystal structure. The RE³⁺ ion is in an eight-coordinated environment involving eight N atoms of four en ligands forming a bicapped trigonal prism. Hydrogen bonds link [RE(en)₄]³⁺, [SbS₄]³⁻ and en species into a three-dimensional structure. The structure determination of 1 and 2 implies that the ionic radii of rare earth metal ions play an important role on the structures of the rare earth metal thioantimonates.     

An Unpredictable Reaction of <Emphasis Type="Italic">t</Emphasis>Bu<Subscript>2</Subscript>PHO·BCl<Subscript>3</Subscript> in the Presence of Water

Abstract  

When a benzene solution of tBu₂PHO·BCl₃ was exposed to air at room temperature, the phosphonium chloride [tBu₂PH₂]Cl was formed together with di-tert-butylphosphinic acid, tBu₂PO(OH). X-ray quality crystals of the hydrochloride [tBu₂PH₂]Cl·HCl were obtained from the reaction solution at room temperature. The hydrochloride [tBu₂PH₂]Cl·HCl crystallizes in the monoclinic space group P2₁ /m, a = 6.3012(7) ?, b = 6.8970(10) ?, c = 14.5011(15) ?, β = 99.376(9)°, V = 621.79(13) ?³, Z = 2, d _calcd = g cm⁻³ 1.165; R1 = 0.0510, wR2 = 0.1503 for 1,129 reflections with I > 2σ(I). The crystal was a non-merohedral twin with a contribution of 0.353(7) of the minor component. The structure is composed of discrete di-t-butylphosphonium cations and Cl anions. Both are located on a crystallographic mirror plane and are connected by P–H···Cl hydrogen bonds.     

Na<Subscript>3</Subscript>Tb<Subscript>3</Subscript>[Si<Subscript>6</Subscript>O<Subscript>18</Subscript>] · H<Subscript>2</Subscript>O,a synthetic analogue of microporous mineral gerenite

Crystals of a new silicate, Na₃Tb₃[Si₆O₁₈] · H₂O, space group \(P\bar 1\), are obtained under hydrothermal conditions. The formula of the compound is determined in the course of structure solution. The silicate is a synthetic analogue of the gerenite mineral (Ca_1.21Na_0.57)(Y_2.24Dy_0.68)Si₆O₁₈ · 2H₂O, whose structure contains six-membered rings formed by SiO₄ tetrahedra. The [Si₆O₁₈] rings are connected by TbO₆ octahedra into a mixed microporous framework with voids filled by Na atoms and water molecules. The new silicate differs from gerenite by the occupation of the Ca position by Na atoms and population of the pores sandwiched between six-membered rings. By virtue of conditions of hydrothermal synthesis in the absence of Ca and excess of Na in the system, an additional Na position appears in the void. It is populated statistically, and in gerenite it was occupied by water molecules only. In the new structure, the position of water is split into two statistically populated positions. The inclusion of Na atoms in additional positions in framework pores and their high thermal vibrations are indicative of ion-exchange properties of the structure. Possible paths of ion exchange are discussed.     

Crystal growth and properties of Rb<Subscript>2</Subscript>Ni(SO<Subscript>4</Subscript>)<Subscript>2</Subscript> · 6H<Subscript>2</Subscript>O (RNSH)

Large single crystals of rubidium nickel hexahydrate Rb₂Ni(SO₄)₂ · 6H₂O (RNSH) of optical quality were grown for the first time. The atomic structure of RNSH crystals was refined. A comparative analysis of the crystal structures of (M ¹⁺)₂Ni(SO₄)₂ · 6H₂O, where M ¹⁺ is K, Rb, or Cs, was performed. The solubility curve of RNSH in water was measured. The optical and thermogravimetric properties of RNSH were investigated. The internal defect structure of RNSH crystals was studied by X-ray topography.     

Synthesis and structure of the [Os<Emphasis Type="Italic">Thio</Emphasis><Subscript>6</Subscript>]Br<Subscript>3</Subscript> · H<Subscript>2</Subscript>O complex

A complex of the composition [OsThio ₆]Br₃ · H₂O is synthesized by the reaction of H₂OsBr₆ with thiourea in a 0.5 M HBr solution. The [OsThio ₆]Br₃ · H₂O complex is characterized using electronic absorption and infrared spectroscopy. The structure of the complex is determined by X-ray diffraction analysis. The crystals are orthorhombic with the unit cell parameters a = 20.510(4) Å, b = 11.186(2) Å, c = 11.892(2) Å, space group Pccn, and Z = 4. The thiourea molecules are coordinated to the osmium atom through the sulfur atom. The osmium atom has an octahedral coordination. The Os-S distances fall in the range 2.39–2.40 Å. The outersphere H₂O molecules and Br^? anions are involved in hydrogen bonds with the NH₂ groups of the thiourea molecules.     

Crystal structure and properties of [OsO<Subscript>2</Subscript>(NH<Subscript>3</Subscript>)<Subscript>4</Subscript>]SO<Subscript>4</Subscript> · H<Subscript>2</Subscript>O

The structure of a single crystal of tetraammindioxoosmium(VI) sulfate [OsO₂(NH₃)₄]SO₄ · H₂O, which is synthesized by the reaction of K₂[OsO₂(OH)₄] with (NH₄)₂SO₄ in an aqueous solution, is investigated using X-ray diffraction analysis. The compound crystallizes in the monoclinic crystal system, space group P2₁/c, a = 13.102(2) Å, b = 6.158(3) Å, c = 11.866(2) Å, β = 98.13(2)°, and Z = 4. The [OsO₂(NH₃)₄]SO₄ · H₂O compound has an island structure. Two crystallographically independent osmium atoms are situated at the centers of symmetry, and their octahedral coordination includes two oxygen atoms and four nitrogen atoms of the ammonia molecules. In both octahedra, the osmyl group is linear. The Os-O distances in the octahedra are identical within the standard deviations [Os(1)-O, 1.762(2) Å; Os(2)-O, 1.769(2) Å]. The Os-N bond lengths vary from 2.082(3) to 2.101(3) Å. The cationic complexes, SO₄ groups, and water molecules are linked via the system of hydrogen bonds. The assignment of the absorption bands in the IR spectrum of the compound synthesized is performed, and its thermal behavior in air is studied.     

Investigation of the structure and properties of K<Subscript>9</Subscript>H<Subscript>7</Subscript>(SO<Subscript>4</Subscript>)<Subscript>8</Subscript> · H<Subscript>2</Subscript>O single crystals

The features of the conductivity of K₉H₇(SO₄)₈ · H₂O single-crystal samples in the temperature range of superprotonic phase transition have been investigated. The K₉H₇(SO₄)₈ · H₂O crystal structure is determined and refined taking into account hydrogen atoms by X-ray diffraction analysis at a temperature of 295 K: monoclinic symmetry, sp. gr. P2₁/c, Z = 4, a = 7.059(1), b = 19.773(1), c = 23.449(1) Å, β = 95.33(1)°, R ₁/wR ₂ = 2.71/1.71. The structural data obtained suggest that the occurrence of high conductivity in K₉H₇(SO₄)₈ · H₂O crystals with an increase in temperature is related to the diffusion of crystallization water and motion of K ions, as well as to the transformation of the system of hydrogen bonds and protonic motion. The stabilization of the high-temperature superprotonic phase and its supercooling to low temperatures are due to the presence of channels for the motion of K ions and slow backward diffusion of water in the crystal.     

New Diphosphopentamolybdate K<Subscript>5</Subscript>[HP<Subscript>2</Subscript>Mo<Subscript>5</Subscript>O<Subscript>23</Subscript>] · 10H<Subscript>2</Subscript>O: Synthesis,Structure, and Characterization

A new diphosphopentamolybdate(VI) K₅[HP₂Mo₅O₂₃] · 10H₂O has been prepared employing solution method and characterized by single crystal X-ray diffraction, energy dispersive analysis, infrared spectroscopy, thermal stability analysis, cyclic voltammetry analysis, and ultraviolet visible spectroscopy. The compound crystallizes in the orthorhombic sp. gr. Pcab: a = 15.9661(10) Å, b = 19.0832(10) Å, c = 20.0970(9) Å, V = 6123.27(10) Å3, Z = 8. The crystal structure contains the polyanion units [HP₂Mo₅O₂₃]^5– around the potassium cations and lattice water. The [HP₂Mo₅O₂₃]^5– subunits are connected together through K?O?Mo bridges and hydrogen bonds. The crystal shape morphology was simulated using the Bravais–Friedel–Donnay–Harker model.     

Synthesis and Crystal Structure of (PzCH<Subscript>2</Subscript>CHOHCH<Subscript>2</Subscript>PzH)·(Ph<Subscript>2</Subscript>SnCl<Subscript>3</Subscript>) (Pz = 3,5-dimethylpyrazol-1-yl)

Abstract  

Reaction of Ph₂SnCl₂ with 1,3-bis(3,5-dimethylpyrazol-1-yl)-2-propanol (L) in a 1:1 ratio yields L(SnPh₂Cl₂)₂ adduct, which partly hydrolyzes to the title complex (C₂₅H₃₁Cl₃N₄OSn, Mr = 628.58) during crystal growing in the air. The title complex is of monoclinic, space group P2₁/n with a = 9.0338(9), b = 17.890(1), c = 17.340(1) ?, β = 95.533(1)^o, V = 2798.9(5) ?³, Z = 4, Dc = 1.492 Mg/m³, λ(MoKα) = 0.71073 ?, μ = 1.224 mm⁻¹, F(000) = 1272, R = 0.023, wR = 0.054 for 4212 observed reflections with I ≥ 2σ(I). The crystal structure indicates that there is no direct interaction between the pyrazolyl ligand and the tin atom, but this complex forms a supramolecular structure through weak intermolecular C–H⋯Cl and O–H⋯Cl hydrogen bonds.     

Crystal structure and properties of K<Subscript>2</Subscript>[OsO<Subscript>2</Subscript>(C<Subscript>2</Subscript>O<Subscript>4</Subscript>)<Subscript>2</Subscript>] · 2H<Subscript>2</Subscript>O

The synthesis and X-ray diffraction study of the compound K₂[OsO₂(C₂O₄)₂] · 2H₂O are performed. The compound crystallizes in the triclinic crystal system, space group P \(\bar 1\), a = 6.545(1) Å, b = 6.835(2) Å, c = 7.595(2) Å, α = 85.76(2)°, β = 65.33(2)°, γ = 71.14(2)°, and Z = 1. The osmium atom is located at the center of symmetry and has a distorted octahedral coordination formed by oxygen atoms: two oxygen atoms of the osmyl group occupy the apical positions [Os-O, 1.730(2) Å], and four oxygen atoms of the oxalate ions lie in the equatorial plane. The K⁺ cation is surrounded by ten oxygen atoms located at different K-O distances in the range from 2.787(2) to 3.158(2) Å. The assignment of the absorption bands in the IR spectrum of K₂[OsO₂(C₂O₄)₂] · 2H₂O is performed. The electronic absorption spectra of the compound are recorded in different solvents, and the thermal behavior in air is studied.     

The Synthesis and Crystal Structure of (Hpy)<Subscript>3</Subscript>[PMo<Subscript>12</Subscript>O<Subscript>40</Subscript>]·2(py)

Abstract  

The novel supramolecular networks based on Keggin-type polyoxoanion, formulated (Hpy)₃[PMo₁₂O₄₀]·2(py) has been synthesized hydrothermally and determined by X-ray diffraction. The compound crystallize in Monoclinic, system with space groups and cell parameters, P2 ₁ /n, a = 10.9370(2) ?, b = 19.586(3) ?, c = 12.5500(2) ?, β = 98.618(2)°, V = 2657.8(6) ?³. Organic fragments and Keggin anions are connected via N–H···N, N–H···O contacts to form interesting 1D zigzag chain. The molecule is stabilized in solid state by electrostatic forces and intermolecular hydrogen-bonding interactions to give the confirmation of guest [PMo₁₂O₄₀]³⁻ inserting in organic host.     

AErP<Subscript>2</Subscript>O<Subscript>7</Subscript> (A = Rb,Cs) and HEuP<Subscript>2</Subscript>O<Subscript>7</Subscript>·3H<Subscript>2</Subscript>O: Crystal Structures,Vibrational Studies and Thermal Behaviours

Abstract  

New diphosphates AErP₂O₇, A = Rb (1), Cs (2), and HEuP₂O₇·3H₂O (3) have been prepared via soft chemistry route from evaporation of aqueous solution. Their crystal structures have been solved by single crystal diffraction data. The compounds (1) and (2) crystallize in the monoclinic space group P2₁/c with the following unit cell dimensions: (1) a = 7.7248(4) ?, b = 10.9342(6) ?, c = 8.6716(3) ?, β = 105.434(4)° and Z = 4; (2) a = 7.9192(4) ?, b = 10.8606(4) ?, c = 8.7684(5) ?, β = 104.317(5)° and Z = 4. Compound (3) crystallises in the triclinic space group P − 1, with the unit cell parameters: a = 6.4036(5) ?, b = 6.8753(6) ?, c = 9.7964(8) ?, α = 81.706(7)°, β = 80.218(7)°, γ = 88.381(7)°. Crystal structure of (1) and (2) consists of 3D open framework built from [ErO₆] octahedra sharing corners with [P₂O₇] units, leading to the formation of channels running along c direction in which A⁺ [A = Rb(1), Cs(2)] ions are located. The compound (3), on the other hand, exhibits a lamellar structure, in which edge-sharing polyhedra of eightfold coordinated europium form chains along [010]. These chains are joined in turn to each others using diphosphates bridges. A network of O–H···O hydrogen bonds reinforces the cohesion of the structure of (3). The diphosphate groups in (1), (2) and (3) adopts an eclipsed configuration. IR and Raman spectra of the three new phosphates show usual signals related to the P₂O₇ diphosphate group and the water molecule. TG and DTA studies were carried out on crystals of (3). The data are correlated to the crystal structures ones.     

Synthesis and crystal structure of [UO<Subscript>2</Subscript>CrO<Subscript>4</Subscript>(C<Subscript>5</Subscript>NH<Subscript>5</Subscript>COO)<Subscript>2</Subscript>(H<Subscript>2</Subscript>O)]·2H<Subscript>2</Subscript>O

Crystals of UO₂CrO₄(C₅NH₅COO)₂(H₂O)] · 2H₂O are synthesized and their structure is studied by X-ray diffraction. The compound crystallizes in the triclinic crystal system. The unit cell parameters are as follows: a = 7.0834(10) Å, b = 10.6358(14) Å, c = 12.9539(17) Å, α = 75.096(2)°, β = 74.490(2)°, and γ = 80.657(2)°; V = 904.1(2) ų, space group P \(\bar 1\), Z = 2, and R = 0.026. The structure is built of [UO₂CrO₄(C₅NH₅COO)₂(H₂O)]₂ centrosymmetric dimers, which are linked into a framework by a system of hydrogen bonds involving inner-sphere and outer-sphere water molecules. The coordination number of the U(VI) atom is seven, and the coordination polyhedron is a pentagonal bipyramid with the oxygen atoms of the uranyl group, two chromate groups, two molecules of isonicotinic acid, and a water molecule at the vertices. The crystal chemical formula of the [UO₂CrO₄(C₅NH₅COO)₂(H₂O)]₂ dimer is represented as AB ² M ₃ ¹ , where AB ² M ₃ ¹ , where A = UO ₂ ²⁺ , B ² = CrO ₄ ^2? , and M ¹ = = C₅NH₄COOH and H₂O.