Synthesis and structural characterisation of new ettringite and thaumasite type phases: Ca6[Ga(OH)6·12H2O]2(SO4)3·2H2O and Ca6[M(OH)6·12H2O]2(SO4)2(CO3)2, M = Mn,Sn

Investigations into the formation of new ettringite-type phases with a range of trivalent and tetravalent cations were carried out to further study the potential this structure type has to incorporate cations covering a range of ionic radii (0.53–0.69 Å). We report the synthesis and structural characterisation of a new ettringite-type phase, Ca₆[Ga(OH)₆·12H₂O]₂(SO₄)₃·2H₂O, which was indexed in space group P31c with the unit cell parameters a = 11.202(2) Å, c = 21.797(3) Å and two new thaumasite-type phases Ca₆[M(OH)₆·12H₂O]₂(SO₄)₂(CO₃)₂, M = Mn, Sn which were indexed in space group P6₃ with the unit cell parameters a = 11.071(5) Å, c = 21.156(8) Å and a = 11.066(1) Å, c = 22.420(1) Å respectively. These new phases show the versatility of the ettringite family of structures to tolerate a large range of cation sizes on the octahedral M site and highlights the preference of tetravalent cations to crystallise with the thaumasite structure over the ettringite structure.     

Synthesis of calcium titanate from [Ca(H2O)3]2[Ti2(O2)2O(NC6H6O6)2]·2H2O as a cheap single-source precursor

Calcium titanate (CaTiO₃) was conveniently synthesized by thermal decomposition of a single-source precursor [Ca(H₂O)₃]₂[Ti₂(O₂)₂O(NC₆H₆O₆)₂]·2H₂O at low temperature. This single-source precursor was characterized by elemental analysis, IR spectrum, thermal gravimetric analysis and X-ray single crystal diffraction. The calcined products at different temperature were further characterized by powder X-ray diffractions and IR spectra. The morphology, microstructure, and crystallinity of the resulting CaTiO₃ materials have been characterized by SEM and TEM. The BET measurement revealed that the CaTiO₃ powders had a surface area of 14.0 m²/g. In addition, the microwave dielectric properties of the resulting CaTiO₃ material have been measured.     

Synthesis and Crystal Structure of Two Decavanadates Cluster Metal Complexes: [Co(H2O)6]2[H2V10O28]·6H2O and (NH4)2[Ca(H2O)7]2[V10O28]

Two new decavanadate metal complexes, [Co(H₂O)₆]₂[H₂V₁₀O₂₈]·6H₂O (1) and (NH₄)₂[Ca(H₂O)₇]₂[V₁₀O₂₈] (2), have been synthesized under hydrothermal condition by using chlorhydric acid as the initiator at 120 °C. The aqueous NaVO₃ solution with an aqueous solution of CoCl₂·6H₂O were used for generating 1 and aqueous CaCl₂·2H₂O and NH₄VO₃ solution were employed for creating 2. Compound 1 consisted of discrete hexa-aqua-cobalt [Co(H₂O)₆]²⁺ cations, [H₂V₁₀O₂₈]⁴⁻ anions and non-coordination water molecules. Compound 2 were composed of hepta-aqua-calcium [Ca(H₂O)₇]²⁺ cations, ammonium NH₄ ⁺ and [V₁₀O₂₈]⁶⁻ anion. For compound 2, the distorted pentagonal bipyramid [Ca(H₂O)₇]²⁺ is uncommon. In the crystal lattice, hydrogen bonds played an important role on connecting cations, anions and non-coordinated water molecules to form the three-dimensional network.     

Synthesis, crystal structure, and thermal analysis of hexahydrogen dodecavanadate of composition [NH3 · H2O]6 · H6[Ca4V12O40] · 6H2O

Dihydrogen dodecavanadate of composition [NH₃ · H₂O]₆ · H₆[Ca₄V₁₂O₄₀] · 6H₂O was synthe-sized and studied by X-ray crystallography and TGA analyses. The crystals are cubic, space group I $\bar 4$ 3m;; unit cell parameters: a = 13.518(2) ?, V = 2470.4(3) ?³, ??_calc = 2.2334 g/cm³, Z = 2.     

Synthesis and crystal structure of the complex [Mg(H2O)2(dmf@CB[6])(bdc)]·DMF·4H2O and the inclusion compound [dmf@CB[6]]·8H2O

The complex [Mg(H₂O)₂(dmf@CB[6])(bdc)]·DMF·4H₂O (1) and the inclusion compound [dmf@CB[6]]·8H₂O (2) were obtained from a mixture of magnesium perchlorate and water (for compound 1) or magnesium oxide and H₂SO₄ (for compound 2), and cucurbit[6]uryl (CB[6]) in the presence of N,N-dimethylformamide (DMF) with the additives of terephthalic or fumaric acid, respectively. X-ray diffraction studies showed that magnesium cation in compound 1 coordinated two oxygen atoms of the CB[6] molecule, one oxygen atom of the terephthalate anion, two molecules of water, and a DMF molecule located inside the cucurbit[6]uryl cavity. When fumaric acid was used instead of terephthalic acid under similar conditions of synthesis, no coordination of magnesium cations to cucurbit[6]uryl molecules took place, rather an inclusion compound of DMF into the macrocyclic cavitand was formed. Compounds 1 and 2 were characterized by X-ray diffraction data, IR spectroscopy, and elemental analysis.     

Syntheses,structural determination,and binding studies of nine-coordinate multinuclear (mnH)2[EuIII(egta)]2·6H2O and binuclear (mnH)4[EuIII2(dtpa)2]·6H2O

Two lanthanide complexes, (mnH)₂[Eu^III(egta)]₂·6H₂O (1) (H₄egta = ethyleneglycol-bis-(2aminoethylether)-N,N,N′,N′-tetraacetic acid) and (mnH)₄[Eu^III₂(dtpa)₂]·6H₂O (2) (H₅dtpa = diethylenetriamine-N,N,N′,N″,N″-pentaacetic acid), have been synthesized and characterized by FT-IR spectroscopy, thermal analysis, and single-crystal X-ray diffraction. X-ray diffraction reveals that 1 is multinuclear nine-coordinate and crystallizes in the monoclinic crystal system with space group C2/c. The obtained cell dimensions are a = 38.513(3)?Å, b = 13.5877(8)?Å, c = 8.7051(5)?Å, β = 99.6780(10)°, and 4490.6(5)?ų. Each methylamine (mnH⁺) cation in 1, through hydrogen bonds, connects three adjacent [Eu^III(egta)]^? anions. The [Eu^III(egta)]^? anions connect one another forming a 1-D multinuclear zigzag chain structure along the c-axis. Complex 2 is nine-coordinate binuclear structure with tricapped trigonal prismatic conformation and crystallizing in the monoclinic crystal system, but with space group P2₁/n. The obtained cell dimensions are a = 9.9132(8)?Å, b = 24.1027(18)?Å, c = 10.7120(10)?Å, β = 109.1220(10)°, and 2418.2(3)?ų. For 2, there are two kinds of methylamine cations (mnH⁺) connecting [Eu^III₂(dtpa)₂]^4? complex anions and lattice waters through hydrogen bonds, leading to formation of a 2-D ladder-like layer structure.     

Syntheses and structures of p-HOOCC6F4COOH · H2O (H2L · H2O) and luminescent coordination polymers [Tb2(H2O)4(L)3 · 2H2O] n and Tb2(Phen)2(L)3 · 2H2O

Compounds p-HOOCC₆F₄COOH · H₂O (H₂L · H₂O), [Tb₂(H₂O)₄(L)₃ · 2H₂O] _n (I), and Tb₂(Phen)₂(L)₃ · 2H₂O (II) are synthesized. According to the X-ray structure analysis data, the crystal structure of H₂L · H₂O is built of centrosymmetric molecules H₂L and molecules of water of crystallization. The crystal structure of compound I is built of layers of coordination 2D polymer [Tb₂(H₂O)₄(L)₃] _n and molecules of water of crystallization. The ligands are the L^2? anions performing both the tetradentate bridging and pentadentate bridging-chelating functions. The coordination polyhedron TbO₉ is a distorted three-capped trigonal prism. Acid H₂L manifests photoluminescence in the UV region (??_max = 368 nm). Compounds I and II have the green luminescence characteristic of the Tb³⁺ ions, and the band with ??_max = 545 nm (transition ⁵ D ₄?? ⁷ F ₅) is maximum in intensity. The photoluminescence intensity of compound II is higher than that for compound I.     

Synthesis and Crystal Structure of [Ni(H2O)6][Ni(H2O)2(C4H2O4)]·4H2O

Reaction of a freshly prepared Ni(OH)_{2?2 x} (CO₃) _x ·yH₂O with maleic acid in H₂O at room temperature afforded [Ni(H₂O)₆][Ni(H₂O)₂(C₄H₂O₄)]·4H₂O, which consists of [Ni(H₂O)₆]²⁺ cations, [Ni(H₂O)₂(C₄H₂O₄)]^2? anions and lattice H₂O molecules. Ni atoms in cations are octahedrally coordinated and Ni atoms in anions are each octahedrally coordinated by bidentate chelating maleato ligands and two water molecules at trans positions. Cations and anions are interlinked by hydrogen bonds to form 1D chains, which are hexagonally arranged and connected by the lattice water molecules. When heated in a flowing argon stream, the compound decomposes, with complete dehydration being followed by dissociation of nickel maleate into NiO and maleic anhydride.     

New 1D and 2D metal oxygen connectivities in Cu(II) succinato and glutarato coordination polymers: [Cu3(H2O)2(OH)2(C4H4O4)2] · 4H2O, [Cu4(H2O)2(OH)4(C4H4O4)2] · 5H2O and [Cu5(OH)6(C5H6O4)2] · 4H2O

Two Cu(II) hydroxo succinates [Cu₃(H₂O)₂(OH)₂(C₄H₄O₄)₂]?·?4H₂O (1) and [Cu₄(H₂O)₂(OH)₄(C₄H₄O₄)₂]?·?5H₂O (2) and one Cu(II) hydroxo glutarate [Cu₅(OH)₆(C₅H₆O₄)₂]?·?4H₂O (3) have been prepared and structurally characterized by single crystal X-ray diffraction methods. They feature 1D and 2D copper oxygen connectivity of elongated {CuO₆} octahedra in “4?+?1?+?1” and “4?+?2” coordination geometries. Within 1, linear trimers of three edge-sharing {CuO₆} octahedra are connected into copper oxygen chains, which are bridged by the anti conformational succinate anions to generate 2D layers with mono terminally coordinating gauche succinate anions on both sides. The layers are assembled into a 3D framework by interlayer hydrogen bonds with lattice H₂O molecules distributed in channels. Different from 1, the principal building units in 2 are linear tetramers of four edge-sharing {CuO₆} octahedra. The tetramers are condensed into copper oxygen chains and the succinate anions interlink them into a 3D framework with triangular channels filled by lattice H₂O molecules. The {CuO₆} octahedra in 3 are edge-shared to form unprecedented 2D inorganic layers with mono terminally coordinating glutarate anions on both sides. Interlayer hydrogen bonding interactions are responsible for supramolecular assembly of the layers into a 3D framework with lattice H₂O molecules in the channels. The inorganic layers in 3 can be described as hexagonal close packing of oxygen atoms with the Cu atoms in the octahedral cavities. The title compounds were further characterized by elemental analyses, IR spectra and thermal analyses.     

Rb[C6H3(COOH)2(COO–)] · [C6H3(COOH)3] · 2H2O: Synthesis,Crystal Structure,and Properties

The salt Rb[C₆H₃(COO)₂(^–)] · [C₆H₃(COOH)₃] · 2H₂O (I) of trimesic acid was synthesized and its thermal stability and conductivity (10^–11 ohm^–1 cm^–1 at 298 K) were measured. Molecular and crystal structures of I were established by X-ray diffraction analysis. Hydrogen bonding system in complex I was detected by IR and Raman spectroscopies. X-ray diffraction data agree with vibration spectroscopy data.     

Synthesis, crystal structure, and thermal stability of [Mo2O4(μ2-O)(C6H4O2)2(H2O)] · (C8H9N2)2 · 2H2O

From hydrothermal treatment of benzene-1,2-diamine, pyrocatechol, and MoO₃ in acetic acid solution, a new compound, [Mo₂(μ₂-O)₂(C₆H₄O₂)₂(H₂O)] · (C₈H₉N₂)₂ · 2H₂O (I), constructed from pyrocatechol chelated dinuclear molybdenum units and 2-methylbenzimidazole has been synthesized. Single-crystal structure analysis reveals that the compound crystallizes in the monoclinic space group P2₁/c with a = 23.365(2), b = 7.2214(5), c = 19.3021(16) β = 97.929(4), V = 3225.6(5), Z = 4, M = 808.46, ρ_c = 1.665 g/cm³, μ(MoK _α) = 0.84 mm^?1, F(000) = 1608, the final R = 0.0622 and wR = 0.1484 for 7385 independent reflections with R _int = 0.0393. Interestingly, an in situ condensation between acetic acid and benzene-1,2-diamine has occurred, and the unexpected 2-methyl-1-H-benzo[d] imidazoles serve as counterions and N-H donors to form stable hydrogen-bond network in the crystal. Furthermore, intermolecular hydrogen bonds are found among the cations, anions and crystalline water molecules. The double nuclear molybdenum units are connected by O-H...O hydrogen bonds with the crystalline water molecules to form one-dimensional chains, and the chains are further joined together by N-H...O to form a quasi-two dimensional structure.     

Synthesis, properties, and thermal decomposition of compounds [Co(En)3][Fe(CN)6] · 2H2O and [Co(En)3]4[Fe(CN)6]3 · 15H2O

Binary complex salts, [Co(En)₃][Fe(CN)6] · 2H₂O and [Co(En)₃]₄[Fe(CN)₆]₃ · 15H₂O, are synthesized. The properties of the salts and their thermolysis in air, dihydrogen, and argon are studied. Oxides of the central ions of the binary complex salts are found to be the thermolysis products in an oxidative atmosphere. Solid solutions (intermetallic compounds) CoFe are the thermolysis products in the reductive atmosphere, whereas intermetallides containing considerable amounts of C and N and an impurity of Co and Fe oxides are the thermolysis products in an inert atmosphere. Gaseous thermolysis products in dihydrogen and argon are NH₃, hydrocarbons, and ethylenediamine.     

Hexaaquachromium(III) trihydrogen isopolyvanadate [Cr(H2O)6]H3[V10O28] · 2H2O: Synthesis and study

Hexaaquachromium(III) trihydrogen isopolyvanadate [Cr(H₂O)₆]H₃[V₁₀O₂₈] · 2H₂O (I) was obtained and examined by mass spectrometry, X-ray powder diffraction, thermogravimetry, and IR and NMR spectroscopy. The crystals are monoclinic, space group $P\bar 1$ a = 7.862(3), b = 8.427(5), c = 5.000(2) Å, β = 96.46(4)°, V = 867.0(3) ų, ρ_calcd = 5.83 g/cm³, Z = 1.     

Synthesis,Structure, and Properties of Cesium Polyuranate [Cs2(H2O)3][(UO2)6O3(OH)8]·2H2O

Russian Journal of General Chemistry - Cesium uranate [Cs2(Н2О)3][(UO2)6O3(OH)8]·2H2O was obtained by reacting hydrated uranium(VI) oxide UO3·2.25H2O with a cesium nitrate...     

Syntheses and Crystal Structures of (H3O)(C3H5N2)[Mn(OH)6 Mo6O18]·3.5H2O and (H3O)3[Co(OH)6Mo6O18]·7H2O

The crystals of the title compounds (H3O)(C3H5N2)[Mn(OH)6Mo6O18]·3.5H2O 1 and (H3O)3[Co(OH)6Mo6O18]·7H2O 2 have been prepared and structurally determined by X-ray single-crystal diffraction. Compound 1 crystallizes in monoclinic, space group C2/c with a = 21.5018(9), b = 10.9331(5), c = 11.8667(5)A,β = 95.3570(10)o, V = 2777.5(2)A3, Z = 4, Dc = 2.802 g/cm3, Mr = 1171.80,μ(MoKα) = 3.173 mm-1, F(000) = 223, the final R = 0.0458 and wR = 0.1041 for 2093 observed reflections (I>2σ(I)); Compound 2 crystallizes in monoclinic, space group P21/c with a = 11.4042(12), b = 10.9481(11), c = 11.6722(12)A, β= 99.948(2)o, V = 1435.4(3)A3, Z = 2, Dc = 2.794 g/cm3, Mr = 1207.80,μ(MoKα) = 3.223 mm-1, F(000) = 1160, the final R = 0.0544 and wR = 0.1066 for 1906 observed reflections (I > 2σ(I)). Both compounds 1 and 2 adopt the Anderson structure, in which the anion is of centrosymmetry and formed by six octahedral edge-sharing MoO6 units surrounding the central MO6 (M = Mn or Co) octahedron.     

Crystal structure of CsLnFe(CN)6·5H2O (Ln=Ce,Pr, Nd), CsCeFe(CN)6·4H2O,and TlTmRu(CN)6·3H2O

We have investigated the crystal structures of CsLnFe(CN)₆·nH₂O (Ln=lanthanide, n=4,5), as well as TlTmRu(CN)₆·3H₂O. These phases can be thought of as derivatives of LnFe(CN)₆·4H₂O, where, simultaneously, an alkali ion (or Tl⁺) is introduced while the valence of Fe is reduced from Fe³⁺ to Fe²⁺. A new arrangement of the structural units is observed in the CsLnFe(CN)₆·5H₂O, where the coordination of the Ln-ion is changed to a bisdisphenoid. The resulting LnN₅O₃ units alternate with Fe(CN)₆ units to form an overall rocksalt-type ralted lattice that accommodates the alkali ions in interstitial sites. Due to the arrangement of the water molecules, a layer structure results.     

Structure of the complex [trans-SnF4(H2O)2· (18-crown-6)· 2H2O]

The molecular and crystal structure of the title complex (I) obtained by addition of tin fluoride in a hydrofluoric acid solution to 18-crown-6 in methanol was investigated by X-ray structure analysis. The crystals are monoclinic, space group P2₁/n, a = 13.497(3), b = 7.806(2), c = 9.892(2) Å, β = 95.57(3)°, Z = 2 for C₁₂H₃₂F₄O₁₀Sn. In the polymer chain, the crown ether molecules alternate with the inorganic complexes [trans-SnF₄(H₂O)₂] and are linked to them by O-H...O type hydrogen bonds involving the intermediate water molecules. The weak C-H...F interactions bind the chains into the layers which are parallel to the xz plane.     

An analysis of the vibrational frequencies and amplitudes of the H5O+2 ion in H4SiW12O40·6H2O (TSA·6H2O) and H3PW12O40·6H2O (TPA·6H2O)

The infrared, Raman and inelastic neutron scattering (INS) spectra of TSA·6H₂O and TPA·6H₂O are in agreement with those expected for the presence of H₅O⁺₂ ions. Force fields for different assignment schemes are compared with the observed vibrational frequencies and the INS spectral profile. All but two schemes are eliminated. Whilst low-resolution INS spectroscopy cannot distinguish between these two schemes, the orientations of the vibrational ellipsoids for one scheme are in better agreement with those reported from low-temperature crystallographic studies of the H₅O⁺₂ ion.