Mg2Na2V10O28·20H2O and Mg3V10O28·28H2O

The crystal structures of dimagnesium disodium decavanadate icosahydrate, Mg₂Na₂V₁₀O₂₈·20H₂O, (I), and trimagnesium decavanadate octacosahydrate, Mg₃V₁₀O₂₈·28H₂O, (II), have been determined by single‐crystal X‐ray diffraction. They crystallize with monoclinic (C2/c) and triclinic () symmetry, respectively. All the Mg²⁺ cations in (I) and (II) are octahedrally coordinated by six water mol­ecules. The Na⁺ cations in (I) are coordinated by three water mol­ecules and three O atoms of the decavanadate anions, and link the latter into a three‐dimensional network. The decavanadate anions in (II) are not linked to one another.     

[TMPA]4[Si8O20] · 34 H2O and [DDBO]4[Si8O20] · 32 H2O are heteronetwork clathrates with 1,1,4,4-tetramethylpiperazinium (TMPA) and 1,4-dimethyl-1,4-diazoniabicyclo[2.2.2]octane (DDBO) guest cations

[TMPA]₄[Si₈O₂₀] · 34 H₂O ( 1 ) and [DDBO]₄[Si₈O₂₀] · 32 H₂O ( 2 ) have been prepared by crystallization from aqueous solutions of the respective quaternary alkylammonium hydroxide and SiO₂. The crystal structures have been determined by single-crystal X-ray diffraction. 1 : Monoclinic, a = 16.056(2), b = 22.086(6), c = 22.701(2) Å, β = 90.57(1)° (T = 210 K), space group C2/c, Z = 4. 2 : Monoclinic, a = 14.828(9), b = 20.201(7), c = 15.519(5) Å, β = 124.13(4)° (T = 255 K), space group P2₁/c, Z = 2. The polyhydrates are structurally related host-guest compounds with three-dimensional host frameworks composed of oligomeric [Si₈O₂₀]^8? anions and H₂O molecules which are linked via hydrogen bonds. The silicate anions possess a cube-shaped double four-ring structure and a characteristic local environment formed by 24 H₂O molecules and six cations (TMPA, [C₈H₂₀N₂]²⁺, or DDBO, [C₈H₁₈N₂]²⁺). The cations themselves reside as guest species in large, irregular, cage-like voids. Studies employing ²⁹Si NMR spectroscopy and the trimethylsilylation method have revealed that the saturated aqueous solutions of 1 and 2 contain high proportions of double four-ring silicate anions. Such anions are also abundant species in the saturated solution of the heteronetwork clathrate [DMPI]₆[Si₈O₁₈(OH)₂] · 48.5 H₂O ( 3 ) with 1,1-dimethylpiperidinium (DMPI, [C₇H₁₆N]⁺) guest cations.     

New Fluoromanganate(III) Hydrates: Mn3F8 · 12H2O and AgMnF4 · 4H2O

Single crystals of fluoride hydrates Mn₃F₈ · 12 H₂O and AgMnF₄ · 4 H₂O have been prepared and characterized by X-ray methods. Mn₃F₈ · 12 H₂O crystallizes in the space group P1 (a = 623.0(3), b = 896.7(4), c = 931.8(4) pm, α = 110.07(2)°, β = 103.18(2)°, γ = 107.54(2)°, Z = 1); AgMnF₄ · 4 H₂O crystallizes in the space group P2₁/m (a = 700.9(2), b = 726.1(1), c = 749.4(3) pm, β = 107.17(3)°, Z = 2). Both structures contain Jahn-Teller-distorted [Mn(H₂O)₂F₄]^? anions as well as crystal water molecules and exhibit a complex hydrogen bond network between anions and cations, i. e. [Mn(H₂O)₆]²⁺ for the first and a polymeric [Ag(H₂O)₂]^? cation for the second compound.     

Zur Kenntnis der Phase BaO · Al2O3 · 7 H2O

On the Compound BaO · Al₂O₃ · 7 H₂O On the basis of investigations using ²⁷Al, ¹H NMR, IR and thermoanalytical methods for the compound BaO · Al₂O₃ · 7 H₂O a constitution as Ba_n[Al₂(OH)₈]_n · 3n H₂O with condensed AlO₆ groups, sharing edges, is proposed. Relations between the Ba/Al ratio and the constitution of anions of barium aluminate hydrates are discussed.     

Die Kristallstruktur des Natriumoxohydroxoaluminathydrates Na2[Al2O3(OH)2] · 1,5 H2O

The Crystal Structure of the Sodium Oxohydroxoaluminate Hydrate Na₂[Al₂O₃(OH)₂] · 1.5 H₂O The crystal structure of the sodium oxohydroxoaluminate hydrate Na₂[Al₂O₃(OH)₂] ·s 1.5 H₂O (up to now described as Na₂O · Al₂O₃ · 2.5 H₂O and Na₂O · Al₂O₃ · 3 H₂O, respectively) was solved. The X-ray single crystal diffraction analysis (tetragonal, space group P-42₁m, a = 10.522(1) Å, c = 5.330(1) Å, Z = 4) results in a polymeric layered structure, consisting of AlO_3/2(OH) tetrahedral groups. Between these layers the Na⁺ ions are situated, which form tetrameric groups of face-linked NaO₆ octahedra. The involved O^2? ions are due to Al? O? Al bridges, Al? OH groups and water of crystallization. ²⁷Al and ²³Na MAS NMR investigations confirm the crystal structure analysis. The relations between the crystallization behaviour of the compound and the constitution of the aluminate anions in the corresponding sodium aluminate solution and in the solid, respectively, are discussed.     

Crystal structures of hydrates of simple inorganic salts. III. Water‐rich aluminium halide hydrates: AlCl3·15H2O,AlBr3·15H2O,AlI3·15H2O,AlI3·17H2O and AlBr3·9H2O

Water‐rich aluminium halide hydrate structures are not known in the literature. The highest known water content per Al atom is nine for the perchlorate and fluoride. The nonahydrate of aluminium bromide, stable pentadecahydrates of aluminium chloride, bromide and iodide, and a metastable heptadecahydrate of the iodide have now been crystallized from low‐temperature solutions. The structures of these hydrates were determined and are discussed in terms of the development of cation hydration spheres. The pentadecahydrate of the chloride and bromide are isostructural. In AlI₃·15H₂O, half of the Al³⁺ cations are surrounded by two complete hydration spheres, with six H₂O in the primary and 12 in the secondary. For the heptadecahydrate of aluminium iodide, this hydration was found for every Al³⁺.     

Cu3V10O28·24H2O and CuNa4V10O28·23H2O

The crystal structures of tricopper decavanadate tetracosa­hydrate, (I), and copper tetra­sodium decavanadate tricosa­hydrate, (II), have been determined by single‐crystal X‐ray diffraction. Both compounds exhibit a catenary structure consisting of [V₁₀O₂₈]⁶⁻ anions linked by Cu²⁺ cations in (I) or by Na⁺ cations in (II). Compound (II) also contains a polymeric linear array of edge‐sharing [Na(OH₂)₆]⁺ and [Cu(OH₂)₆]²⁺ octahedra. In both compounds, the [V₁₀O₂₈]⁶⁻ ions lie about inversion centres and the Cu²⁺ ions in (I) also lie about inversion centers.     

The vitrification of alkali borate and alkali silicate melts

Glasses and crystals of compositions corresponding to the congruently melting compounds M₂O·2SiO₂ (M = Na. Rb, and Cs) and M₂O·4SiO₂ (M = K, Rb, and Cs) were studied by differential scanning calorimetry. The structure temperatures (T _f) and excess entropies at T _f of glasses were measured depending on the rate of cooling of the corresponding melts. The activation energies of glass formation (ΔE) and scale of cooperative motion in the transition region (ξ_a) were estimated. The totality of the data obtained were used to compare the thermodynamic (the ratio between the excess (with respect to the corresponding crystals) entropy of glass at T _f and the entropy of crystal melting), kinetic (fragility m = f(ΔE, T _f)), and microscopic (ξ_a) parameters of the vitrification of alkali silicate melts. The behaviors of alkali silicate and alkali borate melts were shown to be similar.     

Über die quasi-binären Systeme NaNO2/Na2O und NaCN/Na2O. Phasendiagramme und Natrium-Ionenleitung in Na3O(NO2) und Na3O(CN)

On the Quasi-Binary Systems NaNO₂/Na₂O and NaCN/Na₂O. Phase Diagrams and Sodium Ion Conductivity of Na₃O(NO₂) and Na₃O(CN) Measurements of the electrical conductivities of Na₃O(NO₂) and Na₃O(CN) show sharp increases in conductivity at temperatures between 200° and 250°C, According to the phase diagrams of the quasi-binary systems NaNO₂/Na₂O and NaCN/Na₂O this is not an effect established by fusion. It seems to be a consequence of a “melting” of the sodium sublattice or the rotational disorder of complex anions.     

[{Na(7‐Nitro‐5‐sulfonate‐naphthalene‐1,4‐dicarboxy‐acid (H2O)2}·H2O]n: A Water‐Soluble 2D Layer Polymeric Complex with Microporous Molecular Channels

The X‐ray crystallographic studies are reported for a water‐soluble sodium complex of organic acid, {[Na(NSNDC)(H₂O)₂]·H₂O}_n, (NSNDC = 7‐Nitro‐5‐sulfonate‐napthalene‐1,4‐dicarboxy‐acid). It contains layers of vertically oriented NNSDC‐anions sandwiching cations and water molecules. The rows of anions are linked in a direction by sodium ions and along b by hydrogen bonding, which have microporous channels (9.410 × 3.210Ų) along the crystallographic b‐axis. Considering the Na coordination environments, π‐π stacking interaction between aryl ring and hydrogen bonds, the title compound represents a stably 2D infinitely extended structure.     

K2[Hg(SO3)2]·2.25H2O

The characteristic feature of the structure of the title compound, dipotassium bis(sulfito‐κS)mercurate(II) 2.25‐hydrate, is a layered arrangement parallel to (001) where each of the two independent [Hg(SO₃)₂]²⁻ anions are grouped into centrosymmetric pairs and are surrounded by two K⁺ cations to give the overall layer composition {K₂[Hg(SO₃)₂]₂}²⁻. The remaining cations and the uncoordinated water molecules are situated between these layers. Within the [Hg(SO₃)₂]²⁻ anions, the central Hg atoms are twofold coordinated by S atoms, with a mean Hg—S bond length of 2.384 (2) Å. The anions are slightly bent [174.26 (3) and 176.99 (3)°] due to intermolecular O...Hg interactions greater than 2.8 Å. All coordination polyhedra around the K⁺ cations are considerably distorted, with coordination numbers ranging from six to nine. Although the H atoms of the five water molecules (one with symmetry 2) could not be located, O...O separations between 2.80 and 2.95 Å suggest a system of medium to weak O—H...O hydrogen bonds which help to consolidate the structural set‐up. Differences and similarities between the bis(sulfito‐κS)mercurate(II) anions in the title compound and those in the related salts (NH₄)₂[Hg(SO₃)₂] and Na₂[Hg(SO₃)₂]·H₂O are discussed.     

Hydrate schwacher und starker Basen. VII. Zum System Caesiumhydroxid-Wasser: Die Kristallstrukturen von CsOH · 2H2O und CsOH · 3H2O

Hydrates of Weak and Strong Bases. VII. Concerning the System Cesium Hydroxide—Water: The Crystal Structures of CsOH · 2H₂O and CsOH · 3H₂O In the context of structural studies of hydrates of the alkali metal hydroxide the crystal structure of CsOH · 2H₂O and CsOH · 3H₂O have been determined for the first time. The diffractometer data, obtained at -150 · C,made it possible to locate and refine also all the H-atoms. The dihydrate was found to probably form only one phase, melting incongruently at 2,5 · C. It is orthorhombic with space group Pca2₁ and Z = 8 formula units per unit cell. The lattice constants are a = 13.238, b = 6.747 and c = 9.121 A. With 1870 independent observed reflection a final R value of 0.013 was obtained. The trihydrate, melting congruently et -5.5 ·C, is monoclinic with space group P2₁/n,Z = 4 and lattice constants a = 8.637, b = 5.984, c = 10.061 Å and ß = 96.57 ·. With 2098 independent observed reflection the final R is 0.026. In both hydrate structures there are no simple characteristic coordination polyhedra for the cations; in each case it is rather the hydrogen-bonded and fully ordered anionic water structure which shows up as the determining building principle. Both these water structures are altogether three-dimensional, but primarily contain layers. The anionic layers are formed by condensation of small and medium rings, namely four-, five- and seven-membered rings in CsOH · 2H₂O and four-, five- and six membered ones in CsOH · 3H₂O. They are linked together by one set each of extra H₂O molecules between the layers as well as by the Cs⁺ ions.     

Preparation,Crystal Structure and Vibrational Spectra of Ca2P2O6·2H2O and [Ca(H2O)3(H2P2O6)]·0.5(C12H24O6)·H2O

The calcium salts Ca₂P₂O₆ · 2H₂O ( 1 ) and [Ca(H₂O)₃(H₂P₂O₆)] · 0.5(C₁₂H₂₄O₆) · H₂O ( 2 ) were prepared and structurally characterized by single‐crystal X‐ray diffraction. Compound 1 crystallizes in the orthorhombic space group Pbca and compound 2 in the monoclinic space group P2₁/n. The crystal structure of compound 1 consists of chains of edge‐sharing [CaO₇] polyhedra linked by hypodiphosphate(IV) anions to form a three‐dimensional network. The crystal structure of compound 2 consists of alternated layers of crown ether and water molecules and respective ionic units. Within the layers of ionic units the Ca²⁺ cations are octahedrally coordinated by three monodentate dihydrogenhypodiphosphate(IV) anions and three water molecules. The IR/Raman spectra of the title compounds were recorded and interpreted, especially with respect to the [P₂O₆]^4– and [H₂P₂O₆]^2– groups. The phase purity of 2 was verified by powder diffraction measurements.     

Neue Verbindungen im System CaO/SiO2/CaCl2/H2O

New Compounds in the System CaO/SiO₂/CaCl₂/H₂O The hydrothermal formation of novel calcium silicate hydrates of compositions 5 CaO · 2 SiO₂ · CaCl₂ · 4 H₂O, 5 CaO · 2 SiO₂ · CaCl₂ · 2 H₂O and 4 CaO · 2 SiO₂ · CaCl₂ · H₂O from Ca₃SiO₅ and mixtures of CaO and SiO₂, respectively, in presence of calciumchloride at 200°–350 °C is described. From molybdate-reaction, ²⁹Si MAS NMR, DTA and TG measurements it is concluded that these compounds are based on disilicate anions and are to be interpreted as calcium hydroxide disilicate chlorides.     

Supramolecular Networks Extended by N–H···O Interactions between Cu‐Benzimidazole Subunits and Keggin Anions

Three new 2D/3D supramolecular architectures derived from Cu‐organic subunits and Keggin anions, [Cu^II₂(biz)₈(HPMo^VI₁₀Mo^V₂O₄₀)(H₂O)₂] · 2H₂O ( 1 ), [Cu^I₄(biz)₈(SiW₁₂O₄₀)] · 2H₂O ( 2 ) and [Cu^I₂(dmbiz)₄(Hdmbiz)₂(SiW₁₂O₄₀)] ( 3 ) (biz = benzimidazole, dmbiz = 5, 6‐dimethyl benzimidazole), were obtained under hydrothermal conditions. Single crystal X‐ray diffraction analysis reveals that compound 1 has two kinds of [Cu^II(biz)₂]²⁺ cations, which are further extended by Keggin anions into a 2D (4, 8)‐connected supramolecular network by hydrogen bonding interactions. In compound 2 , four types of [Cu^I(biz)₂]⁺ subunits link the [SiW₁₂O₄₀]^4– anions to form a 3D (2, 6)‐connected supramolecular structure. Compound 3 shows a 3D supramolecular network with a NaCl‐type topology constructed by [Cu^I(dmbiz)₂]⁺ subunits, anions, and discrete [Hdmbiz]⁺ cations. Moreover, the electrochemical and photocatalytic properties of compounds 1 and 2 were investigated.     

Barium chlorite hydrate,Ba(ClO2)2·3.5H2O

The structure of barium chlorite hydrate, Ba(ClO₂)₂·3.5H₂O, has been determined by single‐crystal X‐ray analysis at 150 K. The structure is monoclinic, space group C2/c, with Z = 8. It contains layers of Ba²⁺ cations coordinated by ClO₂⁻ anions and water mol­ecules. There are also solvate water mol­ecules involved only in hydrogen bonding of the layers. Three solvate water O atoms are on sites of twofold symmetry, while all other atoms are in general positions. The full coordination environment of the Ba²⁺ cation consists of ten O atoms belonging to six chlorites and three water mol­ecules, forming a bicapped square antiprism.     

Sodium aluminogermanate hydroxosodalite hydrate Na6+x[Al6Ge6O24](OH)x · nH2O (x ≈ 1.6, n ≈ 3.0): Synthesis,phase transitions and dynamical disorder of the hydrogen dihydroxide anion,H3O2−, in the Cubic high-temperature form

Crystalline sodium aluminogermanate hydroxosodalite hydrate Na_6+x[Al₆Ge₆O₂₄](OH)_x · nH₂O with x ≈ 1.6 and n ≈ 3.0 has been synthesized by reacting Al₂O₃, GeO₂ and NaOH solution under hydrothermal conditions, and characterized by means of simultaneous thermal analysis, differential scanning calorimetry, X-ray and neutron diffraction as well as ¹H and ²³Na MAS NMR and IR spectroscopy. The material undergoes a reversible structural phase transition at T_c = 166 K (heating mode), which is actually a complex two-step transformation as detected in DSC measurements. Structure refinements of the cubic high-temperature form (cell constant a = 9.034(2) Å, room temperature) with single-crystal X-ray and powder neutron diffraction data have not yielded overall satisfactory results, probably due to the solid-solution character of the hydrosodalite. The refinements nevertheless demonstrate that (i) the sodalite host framework is a strictly alternating array of corner-linked AlO₄ and GeO₄ tetrahedra, and (ii) most polyhedral [4⁶6⁸] cavities are occupied by four sodium cations and one orientationally disordered hydrogen dihydroxide anion, H₃O₂^?, which possesses a strong central hydrogen bond. Variable-temperature ¹H MAS NMR spectra unambiguously confirm the presence of H₃O₂^? ions and, in addition, reveal a dynamical intraionic exchange between the central and terminal protons and a rotational diffusion of those anions to occur in the high-temperature form. The nature of the guest complexes filling the remaining cages could not be unambiguously determined. Results are compared with those obtained in recent studies on the related sodium aluminosilicate hydrosodalite system of the general formula Na_6+x[Al₆Si₆O₂₄] (OH)_x · nH₂O.     

Na6(H2O)20(V10O28)·4H2O,a novel polyvanadate(V) with a three‐dimensional framework

The novel title polyvanadate(V), poly[[octa‐μ‐aqua‐dodecaaqua‐μ₄‐octacosaoxidodecavanadato‐hexasodium] tetrahydrate], [Na₆(H₂O)₂₀(V₁₀O₂₈)·4H₂O]_n, contains [V₁₀O₂₈]⁶⁻ anions which lie about inversion centres and have approximate 2/m symmetry and which are linked to [Na₃(H₂O)₁₀]³⁺ cations through two terminal and two μ₂‐bridging O atoms. The structure contains three inequivalent Na⁺ cations, two of which form [Na₂(H₂O)₈]_n chains, which are linked via NaO₆ octahedra involving the third Na⁺ ion, thus forming a three‐dimensional framework.     

Na10(glycine)2[H2W12O42]·28H2O

The title compound, decasodium diglycine di­hydro­geno­do­tetra­conta­do­deca­tung­state(10?) octa­cosa­hydrate, consists of a centrosymmetric paratungstate [H₂W₁₂O₄₂]^10? anion, ten Na⁺ cations, two zwitterionic glycine molecules and 28 water molecules of crystallization. Two glycine carboxylate O atoms coordinate three different Na⁺ cations, while the amino N atom forms hydrogen bonds with the paratungstate anion through both terminal and bridging O atoms.     

New coordination modes in potassium edta salts: K2[H2edta]·2H2O,K3[Hedta]·2H2O and K4[edta]·3.92H2O

Three potassium edta (edta is ethylenediaminetetraacetic acid, H₄Y) salts which have different degrees of ionization of the edta anion, namely dipotassium 2‐({2‐[bis(carboxylatomethyl)azaniumyl]ethyl}(carboxylatomethyl)azaniumyl)acetate dihydrate, 2K⁺·C₁₀H₁₄N₂O₈²⁻·2H₂O, (I), tripotassium 2,2′‐({2‐[bis(carboxylatomethyl)amino]ethyl}ammonio)diacetate dihydrate, 3K⁺·C₁₀H₁₃N₂O₈³⁻·2H₂O, (II), and tetrapotassium 2,2′,2′′,2′′′‐(ethane‐1,2‐diyldinitrilo)tetraacetate 3.92‐hydrate, 4K⁺·C₁₀H₁₂N₂O₈⁴⁻·3.92H₂O, (III), were obtained in crystalline form from water solutions after mixing edta with potassium hydroxide in different molar ratios. In (II), a new mode of coordination of the edta anion to the metal is observed. The HY³⁻ anion contains one deprotonated N atom coordinated to K⁺ and the second N atom is involved in intramolecular bifurcated N—H...O and N—H...N hydrogen bonds. The overall conformation of the HY³⁻ anions is very similar to that of the Y⁴⁻ anions in (III), although a slightly different spatial arrangement of the –CH₂COO⁻ groups in relation to (III) is observed, whereas the H₂Y²⁻ anions in (I) adopt a distinctly different geometry. The preferred synclinal conformation of the –NCH₂CH₂N– moiety was found for all edta anions. In all three crystals, the anions and water molecules are arranged in three‐dimensional networks linked via O—H...O and C—H...O [and N—H...O in (I) and (II)] hydrogen bonds. K...O interactions also contribute to the three‐dimensional polymeric architecture of the salts.