Bismuth aluminoborate Bi<Subscript>0.96</Subscript>Al<Subscript>2.37</Subscript>(B<Subscript>4</Subscript>O<Subscript>10</Subscript>)O: Synthesis and crystal structure

The crystal structure of a new bismuth aluminoborate Bi_0.96Al_2.37(B₄O₁₀)O is studied by single-crystal X-ray diffraction. The Bi_0.96Al_2.37(B₄O₁₀)O single crystals are hexagonal (space group \(P\bar 6\) 2m). The unit cell parameters are as follows: a = b = 4.587(4) Å, c = 2.253(9) Å, α = β = 90°, γ = 120°, V = 168.60 ų, Z = 1.     

Structure of bismuth oxoborate Bi<Subscript>4</Subscript>B<Subscript>2</Subscript>O<Subscript>9</Subscript> at 20, 200, and 450°C

Single crystals of bismuth oxoborate Bi₄B₂O₉ have been grown by slowly cooling the melt of a stoichiometric Bi₂O₃ + H₃BO₃ mixture. The structure of the borate (monoclinic space group P2₁/c, a = 11.107 Å, b = 6.629 Å, c = 11.044 Å, β = 91.04°, Z = 4) has been studied at 20, 200, and 450°C. The structure is described not only in terms of full BiO₆ ^? and BiO₇ polyhedra but also in terms of truncated BiO₃ ^? and BiO₄ ^? polyhedra and BO₃ triangles, as well as oxo-centered OBi₃ triangles and OBi₄ tetrahedra. It is shown that both the B-O and Bi-O bond lengths are practically unaffected by temperature. Only the angles between polyhedra change with temperature, being responsible for the strong anisotropy of Bi₄B₂O₆ thermal expansion, which was measured by high-temperature powder X-ray diffraction: α₁₁ = 20, α₂₂ = 15, α₃₃ = 6 × 10^?6 °C^?1, and μ = (c, α₃₃) = ?19°.     

Untersuchungen zu Bismutseltenerdoxidhalogeniden der Zusammensetzung Bi2SEO4X (X = Cl,Br, I)

Investigations on the Bismuth Rare‐Earth Oxyhalides Bi₂REO₄X (X = Cl, Br, I) Compounds of the composition of Bi₂REO₄X (RE = Y, La–Lu; X = Cl, Br, I) have been prepared by solid state reaction of stoichiometric mixtures of BiOX, Bi₂O₃, and RE₂O₃. They were characterized by X‐ray powder diffraction, IR spectroscopy, mass spectrometry and DTA/TG measurements as well. The crystal structure (tetragonal, P4/mmm, a ≈ 3.9 Å, c ≈ 9 Å) was determined by the Rietveld method. In the structure [M₃O₄]⁺ layers are interleaved by single halogen layers. Rare‐earth and bismuth atoms in Bi₂REO₄X are 8‐coordinated. The structure can be derived from the LiBi₃O₄Cl₂ type structure. The enthalpies of formation are derived from heats of solution. The standard entropies were calculated from low‐temperature measurements of the specific heat capacities.     

On the structure of evaporated bismuth oxide thin films

The bismuth oxide films evaporated from bulk Bi₂O₃ are shown to vary in stoichiometry. The as-evaporated low rate (1–5 Å/sec) films are microcrystalline and bismuth rich, relative to Bi₂O₃, and their optical absorption edge broadens and shifts to lower energies. High rate (15–25 Å/sec) films are morphous and oxygen-rich with an absorption edge shifted to higher energies. Thermal decomposition of the Bi₂O₃ during evaporation produces the variations in film stoichiometry. The high temperature δ-Bi₂O₃ observed in the as-evaporated low rate films and thermally treated amorphous films indicates the melt and the films are structurally similar. Thermal treatment of the low rate films results in the formation of the β-form. Comparison of X-ray and stoichiometry results suggests that β-Bi₂O₃ be expressed as β-Bi₂O_±3x, where x is the deviation from trioxide stoichiometry.     

The phase relations in the In2O3A2O3BO systems at elevated temperatures [A: Fe or Ga, B: Cu or Co]

The phase relations in the In₂O₃Fe₂O₃CuO system at 1000°C, the In₂O₃Ga₂O₃CuO system at 1000°C, the In₂O₃Fe₂O₃CoO system at 1300°C, and the In₂O₃Ga₂O₃CoO system at 1300°C were determined by means of a classical quenching method. InFeCuO₄ (a = 3.3743(4) Å, c = 24.841(5) Å), InGaCuO₄ (a = 3.3497(2) Å, c = 24.822(3) Å), and InGaCoO₄ (a = 3.3091(2) Å, c = 25.859(4) Å) having the YbFe₂O₄ crystal structure, In₂Fe₂CuO₇ (a = 3.3515(2) Å, c = 28.871(3) Å), In₂Ga₂CuO₇ (a = 3.3319(1) Å, c = 28.697(2) Å), and In₂FeGaCuO₇ (a = 3.3421(2) Å, c = 28.817(3) Å) having the Yb₂Fe₃O₇ crystal structure, and In₃Fe₃CuO₁₀ (a = 3.3432(3) Å, c = 61.806(6) Å) having the Yb₃Fe₄O₁₀ crystal structure were found as the stable ternary phases. There is a continuous series of solid solutions between InFeCoO₄ and Fe₂CoO₄ which have the spinel structure at 1300°C. The crystal chemical roles of Fe³⁺ and Ga³⁺ in the present ternary systems were qualitatively compared.     

Bi2(IO3)(IO6): First combination of [IO3]− and [IO6]5− anions in three-dimensional framework

A new bismuth (III) iodate periodate, Bi₂(IO₃)(IO₆) was obtained from hydrothermal reactions using Bi(NO₃)₃·5H₂O, and H₅IO₆ as starting materials. Bi₂(IO₃)(IO₆) crystallizes in the monoclinic space group P2₁/c (No. 14) with lattice parameters ɑ = 8.1119(6), b = 5.4746(4), c = 16.357(1) Å, β = 99.187(2)°, V = 717.07(9) ų, Z = 4. The structure of Bi₂(IO₃)(IO₆) features a three-dimensional framework which is a combination of [Bi(1)O₅] tetragonal pyramids, [Bi(2)O₈] bicapped trigonal prisms and [IO₃]⁻ and [IO₆]⁵⁻ anions. Thermal analysis shows that the compound is thermally stable up to about 350 °C. The solid state UV-vis-NIR diffuse reflectance spectrum indicates that Bi₂(IO₃)(IO₆) is a semiconductor with a band gap of 2.76 eV.     

Synthesis,thermal analysis,IR spectra,and crystal structure of ammonium 9-molybdomanganate

Ammonium 9-molybdomanganate (NH₄)₆[MnMo₉O₃₂]·6H₂O was synthesized and studied by single-crystal and powder X-ray diffraction, thermogravimetric analysis and IR spectroscopy. The crystals are trigonal, space group R32, a = 15.926(2) Å, c = 12.398(2) Å, V = 2723.3(7) ų, M = 1646.75, Z = 3, ρ(calcd) = 2.98 g/cm³.     

Synthesis and Study of Heterometallic Co–Bi Compounds Based on Ethylenediaminetetraacetic Acid. Crystal and Molecular Structures of [Co(DH)2(o-NH2C6H4CH3)2]2[Bi2(μ-Edta)2(H2O)2] · 10H2O (DH2 is dimethylglyoxime)

Compounds of the [Co(DH)₂A₂](BiEdta) · 6H₂O type (where DH is the monodeprotonated dimethylglyoxime ^–ON=C(CH₃)–(CH₃)C=NOH; A is the o-, m-, or p-toluidine; and Edta is the ethylenediaminetetraacetate(4–) ion) were synthesized and studied. The composition and structures of the complexes were determined from their UV and ¹H NMR spectra and from X-ray diffraction data. The isomer [Co(DH)₂(o-NH₂C₆H₄CH₃)₂]₂[Bi₂(μ-Edta)₂(H₂O)₂] · 10H₂O was structurally characterized using X-ray diffraction analysis. The crystals are triclinic: a = 12.153(2) Å, b = 12.824(3) Å, c = 16.215(3) Å, α = 67.73(3)°, β = 86.18(3)°, γ = 66.96(3)°, space group P $\overline 1$ , ρ(calcd) = 1.719 g/cm³, Z = 4. The structure is composed of complex binuclear [Bi₂(μ-Edta)₂(H₂O)₂]^2– anions, [Co(DH)₂(o-NH₂C₆H₄CH₃)₂]⁺ cations, and molecules of crystallization water. The Edta^4– anion chelates with the Bi atom in a hexadentate manner (N₂O₄); the fifth O atom functions as a bridging ligand. The bismuth coordination polyhedron can be regarded as a strongly distorted antiprism. In the octahedral cation, the Co(III) atom coordinates four N atoms of two DH ligands (average Co–N 1.897 Å) and two N atoms of two o-toluidine molecules (Co–N 2.023 Å). Thermolysis of the complexes studied was found to proceed in several successive steps, namely, the deaquation, deamination, and pyrolysis of the ligands.     

Bismuth triple-decker phthalocyanine: synthesis and structure

Triclinic crystals of bismuth(III) triple-decker phthalocyanine, Bi₂Pc₃, Pc=C₃₂H₁₆N₈²⁻, were grown directly by the reaction of Bi₂Se₃ with 1,2-dicyanobenzene at 220°C. The Bi₂Pc₃ molecule is centrosymmetric with the bismuth atoms located closer to the peripheral phthalocyaninato(2−) rings than to the central ring. Each bismuth(III) ion is connected by four N-isoindole atoms to the peripheral and by four N-isoindole to the central Pc ring with average distances of 2.333 and 2.747 Å, respectively. This indicates a stronger connection of Bi(III) to the peripheral saucer-shaped macrocyclic rings than to the central rings. The neighbouring phthalocyaninato(2−) moieties in the Bi₂Pc₃ molecule are separated by a distance of 3.101(5) Å. The central Pc ring is rotated by 36.4° with respect to the peripheral ones. Differences in Bi–N bond lengths are a result of interaction of the bismuth ion with peripheral and central rings as well as the repulsion forces between two bismuth ions in the same Bi₂Pc₃ molecule, which are separated by a distance of 3.839(2) Å. The crystal packing is characterized by a distance of 3.56 Å between Pc rings of neighbouring Bi₂Pc₃ molecules.     

Crystal structure of [Pb<Subscript>3</Subscript>(OH)<Subscript>4</Subscript>Co(NO<Subscript>2</Subscript>)<Subscript>3</Subscript>](NO<Subscript>3</Subscript>)(NO<Subscript>2</Subscript>)·2H<Subscript>2</Subscript>O

The structure of [Pb₃(OH)₄Co(NO₂)₃](NO₃)(NO₂)·2H₂O is determined by single crystal X-ray diffraction. The crystallographic characteristics are as follows: a = 8.9414(4) Å, b = 14.5330(5) Å, c = 24.9383(9) Å, V = 3240.6(2) ų, space group Pbca, Z = 8. The Co(III) atoms have a slightly distorted octahedral coordination formed by three nitrogen atoms belonging to nitro groups (Co–N_av is 1.91 Å) and three oxygen atoms belonging to hydroxyl groups (Co–O_av is 1.93 Å). The hydroxyl groups act as μ₃-bridges between the metal atoms. The geometric characteristics are analyzed and the packing motif is determined.     

High n-value phases in the complex bismuth oxides with layered structure,Bi2CaNan−2NbnO3n+3

Complex bismuth oxides with layered structure are prepared with a series of compositions in the system Bi₂CaNb₂O₉-NaNbO₃. It is found by X-ray powder diffraction that each compound is composed of more than two phases, which are described by a formula Bi₂CaNa_n?2Nb_nO_3n+3, e.g., in the sample with the nominal composition Bi₂CaNb₂O₉ · 8NaNbO₃, the phases with n = 6 to 8 appear predominantly. These phases are closely intergrown to each other. Moreover, high-resolution electron microscopy reveals that microsyntactic intergrowth frequently occurs in the phases with n > 5. The occurrence of the latter intergrowth is explained in terms of the bond length obtained.     

Synthesis and study of hexamolybdenochromate(III) with the amminenickel cation: Ni(NH3)4 · H[CrMo6O18(OH)6)] · 10H2O

Hexamolybdenochromate(III) with the amminenickel cation, Ni(NH₃)₄ · H[CrMo₆O₁₈(OH)₆] · 10H₂O, is synthesized and studied by X-ray diffraction, IR spectroscopy, and termogravimetry. The crystals are triclinic: a = 17.67 Å, b = 14.87 Å, c = 10.54 Å, α = 131.81°, β = 66.08°, γ = 138.42°, V = 1345.09 ų, ρ_calcd = 3.067 g/cm³, Z = 2.     

Crystal structure of the pyrovanadate K4V2O7

The crystal structure of anhydrous K₄V₂O₇ (I) is determined by powder X-ray diffraction. The compound crystallizes in the monoclinic system (a = 10.222(1) Å, b = 6.2309(8) Å, c = 7.282(1) Å, β = 101.31(1)°, space group C2/m, Z = 2). The structure contains layers of isolated V₂O₇ pyrovanadate groups separated by layers of potassium cations. The hydration and dehydration of I are studied by thermal analysis and high-temperature X-ray diffraction. The dehydration is accompanied by decomposition of the starting crystal hydrate to give intermediate compounds. Anhydrous compound I undergoes a reversible phase transition at 740°C. The high-temperature phase is assumed to have a hexagonal unit cell (a = 6.169(4) Å, c = 15.72(1) Å, Z = 2).     

Ein Beitrag zur Kristallstruktur von CuYW2O8, CuHoW2O8 und CuYbW2O8

A Contribution on the Crystal Structure of CuYW₂O₈, CuHoW₂O₈, and CuYW₂O₈ Single crystals of (I) CuY₂O₈, (II), CuHoW₂O₈, and (III) CuYbW₂O₈ were prepared and investigated by X-ray technique. (I) crystallizes with triclinic symmetry, space group C? P1 (a = 5.939 Å, b = 6.042 Å, c = 5.025 Å; α = 112.30°, β = 111.77°; Z = 1). (II) and (III) belong to monoclinic symmetry, space group C? P2/n (II) (a = 10.045 Å, b = 5.808 Å, c = 5.021 Å; β = 94.38°; z = 2 (III) a = 9.948 Å, b = 5.824 Å, c = 5.008 Å; β = 93.36°; Z = 2). The crystal structures will be discussed with respect to other to copper rare earth tungstates.     

Sm2O3Ga2O3 and Gd2O3Ga2O3 phase diagrams

Four definite compounds exist in the Sm₂O₃Ga₂O₃ binary phase diagram, namely: Sm₃GaO₆, Sm₄Ga₂O₉, SmGaO₃, and Sm₃Ga₅O₁₂. The $\text{3}\text{1}$ compound is orthorhombic (space group Pnna - Z.4) with the cell parameters: a = 11.40₀Å, b = 5.51₅Å, c = 9.07Å and belongs to the oxysel family. Sm₃GaO₆ and SmGaO₃ melt incongruently at 1715 and 1565°C; Sm₄Ga₂O₉ and Sm₃Ga₅O₁₂ have a congruent melting point at 1710 and 1655°C. With regard to the Gd₂O₃Ga₂O₃ system three definite compounds have been identified: Gd₃GaO₆, Gd₄Ga₂O₉, and Gd₃Ga₅O₁₂. Only the garnet melts congruently at 1740°C with the following composition: Gd_3.12Ga_4.88O₁₂. Gd₃GaO₆, and Gd₄Ga₂O₉ melt incongruently at 1760 and 1700°C. GdGaO₃ is only obtained by melt overheating which may yield an equilibrium or a metastable phase diagram.     

Ag3BiO3 und Ag5BiO4, die ersten Silberoxobismutate(III)

Ag₃BiO₃ and Ag₅BiO₄,the first Silver Oxobismuthates(III) Applying high oxygen pressures (100 MPa) Ag₃BiO₃ and Ag₅BiO₄ were prepared for the first time by reacting the binary components Ag₂O and Bi₂O₃ at temperatures between 770 and 800 K. Single crystals of both compounds were grown hydrothermally from Ag₂O and Bi₂O₃ at 620 K and at oxygen pressures of 10 MPa. The crystal structure determination (Ag₃BiO₃: I4₁, a = 14.1924(1), c = 8.7997(1) Å, Z = 16, 1 729 diffractometer data, R_w = 0.057; Ag₅BiO₄: P2₁/n, a = 5.855(1), b = 8.984(1), c = 12.457(1) Å, β = 91.49(1)Å, Z = 4, 2716 diffractometer data, R_w = 0.036) shows that in Ag₅BiO₄ bismuth approximately has a square pyramidal coordination by five oxygen atoms. Two such pyramids share an edge thus forming ‘isolated’ Bi₂O₈^10? anions. In Ag₃BiO₃ the same groups are linked by the terminal oxygen atoms to form a three dimensional network. In both structures the cation arrangements form variants of the Laves-phases MgCu₂ with silver occupying the copper positions. The Mg positions are ordered occupied by bismuth and silver.     

Reactions of bismuth iodide with ammonium,phosphonium, and bismuthonium salts

The reactions of ammonium, phosphonium, and bismuthonium salts with bismuth iodide were used to synthesize a series of complex compounds with bismuth-containing anions: [(HOC₂H₄)₃NH]⁺ ₄[Bi₄I₁₆]^4?, [Ph₃EtP] ₃ ⁺ [Bi₂I₉]^3?, and [Ph₄Bi] ₃ ⁺ [Bi₅I₁₈]^3?. X-ray diffraction data show that the nitrogen atoms in the two types of crystallographically independent cations of the nitrogen-containing complex possess a distorted tetrahedral coordination [the CNC angles are 110.3(9)°–113.2(9)°]. In the tetranuclear centrosymmetric [Bi₄I₁₆]^4? anion, the bismuth atoms have an octahedral coordination: Two types of groups, BiI₂ and BiI₃, are bound with one another by four μ₂-and two μ₃-iodine bridges (the Bi-I-μ₂, Bi-I-μ₃, and Bi-I-μ₁ distances are 3.1296(10), 3.2808(8); 3.3210(8) and 2.8670(8)–2.9108(9) Å, respectively). The coordination of the phosphorus atom in the [Ph₃EtP]⁺ cations of the phosphorus-containing complex is close to tetrahedral (the CPC angles are 107.5°–114.1°). In the binuclear [Bi₂I₉]^3? anions, the bismuth atoms have an octahedral coordination. The axial I-Bi-I angles are 167.52(2)°, 169.84(2)°, and 174.97(2)°. The terminal BiI₃ fragments [Bi²-I^7,8,9 2.9238(7), 2.9236(7), and 2.9522(7) Å] are in the eclipsed conformation.     

Crystal Structure Determination of Tetrabarium‐digalliumoxide,Ba4Ga2O7

Single crystals of a new barium oxogallate were obtained by growth from a melt at 1500 °C. The compound is monoclinic, with cell parameters a = 17.7447(10) Å, b = 10.6719(5) Å, c = 7.2828(5) Å, β = 98.962(7)°, V = 1362.3(2) ų. The diffraction pattern shows systematic absences corresponding to the space group P12₁/c1. The structure was solved by direct methods followed by Fourier syntheses, and refined using a single crystal diffraction data set (R1 = 0.032 for 2173 reflections with I > 2σ(I)). The chemical composition derived from structure solution is Ba₄Ga₂O₇, with a unit cell content of Z = 6. Main building units of the structure are GaO₄ tetrahedra sharing one oxygen atom to form Ga₂O₇ groups. The Ga–O–Ga bridging angle of one of the two symmetrically independent groups is linear by symmetry. The dimers are crosslinked by barium cations coordinated by six to eight oxygen ligands.     

Refinement of LiFe<Subscript>5</Subscript>O<Subscript>8</Subscript> crystal structure

The crystal structure and the formation conditions of crystals of the LiFe₅O₈ ordered phase obtained from the solution-melt of the Bi₂O₃-Fe₂O₃-B₂O₃-LiCl quadruple system are refined. The crystals are black, octahedral, of cubic symmetry (space group P4₃32). Unit cell parameters: a = 8.3339(1) Å, V = 578.82(1) ų, Z = 4, d _calc = 4.753 g/cm³. From 6046 of the collected array I _hkl 358 are independent (R _int = 0.0321). As a result of anisotropic refinement of structural parameters, R ₁ factor is found to be 0.0186 (wR ₂ = 0.0467). Lithium atoms are in octahedral environment, Li-O is 2.109(1) Å; iron atoms are of two types: in octahedra with Fe-O (by two) distances of 1.9586(9) Å, 2.0152(9) Å, and 2.0652(10) Å and tetrahedra with Fe-O (three) 1.8848(10) Å and 1.914(2) Å. The structure is of inverted spinel type.     

Structure of Aqueous Gallium(III) Bromide Solutions Over a Temperature Range 80–333 K by Raman Spectroscopy, X-ray Absorption Fine Structure, and X-ray Diffraction

The structure and complex formation of concentrated aqueous gallium(III) bromide (GaBr₃) solutions have been investigated over a temperature range 80–333 K by Raman spectroscopy, X-ray absorption fine structure (XAFS), and X-ray diffraction. The Raman spectra obtained at various [Br^?]/[Ga³⁺] molar ratios and temperatures have shown that complex formation between Ga³⁺ and Br^? occurs as a predominant species, with [GaBr₄]^? at [Ga³⁺] as high as 1～2 M (M = mol?dm ^?3) and [Br^?]/[Ga³⁺] ratios > ～2, and that cooling of the solutions favors the formation of the aqua Ga³⁺. The intermediate species were not seen in the Raman spectra. The XAFS data have revealed that the aqua complex has a sixfold coordination as [Ga(H₂O)₆]³⁺ with a Ga³⁺–H₂O distance of (1.96 ± 0.02) Å, whereas the [GaBr₄]^? complex has a Ga³⁺–Br^? distance of (2.33± 0.02) Å, and that vitrification of the aqueous GaBr₃ solution at liquid nitrogen temperature shifts the equilibrium toward the aqua complex. The X-ray diffraction data at different subzero temperatures have shown a tendency of decreasing Ga³⁺–Br^? and increasing Ga³⁺–H₂O interactions with lowering temperature, confirming the preference of aqua Ga³⁺ in the supercooled liquid state as well as in the glassy state. The Ga³⁺–H₂O distance of ～1.8 Å for the tetrahedral coordination was found in a 2.01 M gallium(III) bromide solution with a [Br^?]/[Ga³⁺] ratio of 3.7 and gradually increased to a value of 1.92 Å for octahedral geometry with decreasing temperature, suggesting that equilibrium shifts from [GaBr₄]^? to [Ga(H₂O)₆]³⁺ through intermediate species, [GaBr _n ]^(3?n)+ (n = 2 and 3). The Ga³⁺–Br^? and Br^?–Br^? distances within [GaBr₄]^? with an almost tetrahedral symmetry are (2.35± 0.02) and (3.82± 0.03) Å, respectively. The Ga³⁺ has the second hydration shell at (4.03± 0.03) Å and the hydration of Br^? is characterized with a Br^?–H₂O distance of (3.35± 0.02) Å at all temperatures investigated.