Na2Co(H2PO4)4·4H2O

In the title compound, disodium cobalt tetrakis­(dihydrogen­phosphate) tetrahydrate, the Co^II ion lies on an inversion centre and is octahedrally surrounded by two water molecules and four H₂PO₄ groups to give a cobalt complex anion of the form [Co(H₂PO₄)₄(OH₂)]^2?. The three‐dimensional framework results from hydrogen bonding between the anions. The relationship with the structures of Co(H₂PO₄)₂·2H₂O and K₂CoP₄O₁₂·5H₂O is discussed.     

Synthese und Kristallstruktur von K2(HSO4)(H2PO4), K4(HSO4)3(H2PO4) und Na(HSO4)(H3PO4)

Synthesis and Crystal Structure of K₂(HSO₄)(H₂PO₄), K₄(HSO₄)₃(H₂PO₄), and Na(HSO₄)(H₃PO₄) Mixed hydrogen sulfate phosphates K₂(HSO₄)(H₂PO₄), K₄(HSO₄)₃(H₂PO₄) and Na(HSO₄)(H₃PO₄) were synthesized and characterized by X‐ray single crystal analysis. In case of K₂(HSO₄)(H₂PO₄) neutron powder diffraction was used additionally. For this compound an unknown supercell was found. According to X‐ray crystal structure analysis, the compounds have the following crystal data: K₂(HSO₄)(H₂PO₄) (T = 298 K), monoclinic, space group P 2₁/c, a = 11.150(4) Å, b = 7.371(2) Å, c = 9.436(3) Å, β = 92.29(3)°, V = 774.9(4) ų, Z = 4, R₁ = 0.039; K₄(HSO₄)₃(H₂PO₄) (T = 298 K), triclinic, space group P 1, a = 7.217(8) Å, b = 7.521(9) Å, c = 7.574(8) Å, α = 71.52(1)°, β = 88.28(1)°, γ = 86.20(1)°, V = 389.1(8)ų, Z = 1, R₁ = 0.031; Na(HSO₄)(H₃PO₄) (T = 298 K), monoclinic, space group P 2₁, a = 5.449(1) Å, b = 6.832(1) Å, c = 8.718(2) Å, β = 95.88(3)°, V = 322.8(1) ų, Z = 2, R₁ = 0,032. The metal atoms are coordinated by 8 or 9 oxygen atoms. The structure of K₂(HSO₄)(H₂PO₄) is characterized by hydrogen bonded chains of mixed H_nS/PO₄^– tetrahedra. In the structure of K₄(HSO₄)₃(H₂PO₄), there are dimers of H_nS/PO₄^– tetrahedra, which are further connected to chains. Additional HSO₄^– tetrahedra are linked to these chains. In the structure of Na(HSO₄)(H₃PO₄) the HSO₄^– tetrahedra and H₃PO₄ molecules form layers by hydrogen bonds.     

Structure cristalline de (NH4)2PO3H,H2O: Stereochimie de l'Ion PO3H2− et ses relations avec PO3F2− et SO32−

(NH₄)₂PO₃H, H₂O crystallizes in the monoclinic system, space group P2₁/c, with a = 6.322(1) Å, b = 8.323(1) Å, c = 12.676(1) Å, β = 98.84(1) and Z = 4. The structure was refined to R = 0.022 based on 853 independent X-Rays intensities. Improved dimensions of the tetrahedral PO₃H^2? ion have been obtained: P?H = 1.34(2) and P?O = 1.514(2) Å. The geometry of this ion is compared with that of PO₃F^2? and SO₃^2? ions and we find a decrease of the volume: V_F? > V_H+ > V_{lone pair}.     

Proton transport in polybenzimidazole blended with H3PO4 or H2SO4

Proton transport in H₃PO₄‐ and H₂SO₄‐blended polybenzimidazoles (PBIs) has been studied with both temperature‐ and pressure‐dependent dielectric spectroscopy. The influences of the acid concentration and temperature on the relative conductance and activation volume are discussed. An Arrhenius relation is used to model the temperature‐dependent conductivity at a constant acid content. The logarithm of the relative conductance for PBI blended with H₃PO₄ decreases linearly with increasing pressure. As the temperature increases, the activation volume becomes smaller for PBI blended with H₃PO₄. It is proposed that proton transport in acid‐blended PBI is mainly controlled by proton hopping and diffusion rather than a mechanism mediated by the segmental motions in the polymer. The conductivities of PBIs blended with H₃PO₄ and H₂SO₄ are compared. At a 1.45 molar acid doping concentration, the former has the higher conductivity. With water, the conductivity of H₃PO₄‐blended PBI increases significantly. © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 40: 663–669, 2002; DOI 10.1002/polb.10132     

Preparation and Crystal Structure of Potassium Iron Hydrogen Phosphate,KFe3(HPO4)2(H2PO4)6 · 4 H2O

Single crystals of potassium iron hydrogen phosphate, KFe₃(HPO₄)₂(H₂PO₄)₆ · 4 H₂O, were prepared hydrothermally by heating a mixture of Fe₂O₃, H₃PO₄ and K₂CO₃ with a small amount of water. It crystallizes monoclinic, space group C2/c (N° 15 Int. Tab.) with Z = 4 and a = 1701(2), b = 960.4(5), c = 1750(1) pm, β = 90.88(7)°. The crystal structure was solved by using 1716 unique reflections F₀ > 4σ(F₀) with a final wR2 value of 0.126 (SHELXL-93). The main feature of the crystal structure are layers formed by PO₄-tetrahedra around the FeO₆-octahedra parallel to (001). K⁺ and H₂O molecules connect these layers. Effective Coordination Numbers (ECoN), Mean Fictive Ionic Radii (MEFIR), Charge Distribution (CHARDI) and the Madelung Part of Lattice Energy (MAPLE) are calculated for the title compound. The existence of hydrogen bonds is confirmed by these calculations.     

A Cheap and Efficient Methodology for the Solvent‐Free,One‐pot and Multi‐component Synthesis of 3,4‐Dihydropyrimidin‐2(1H)‐ones Catalyzed by Mesoporous NH4H2PO4/MCM‐48 and Comparison of Its Catalytic Efficacy with NH4H2PO4/MCM‐41

The catalytic efficiency of ammonium dihydrogenphosphate was evaluated in the two heterogeneous forms of NH₄H₂PO₄/MCM‐48 and NH₄H₂PO₄/MCM‐41, as mesoporous catalysts, in the solvent free synthesis of 3,4‐dihydropyrimidin‐2(1H)‐ones through one‐pot three‐component condensation of ethyl acetoacetate, an aryl aldehyde and urea. Different reaction parameters including catalytic efficacy, solvent effect, and urea concentration are considered.     

Synthese und Kristallstruktur der Übergangsmetalltrimetaphosphimate Zn3[(PO2NH)3]2 · 14 H2O und Co3[(PO2NH)3]2 · 14 H2O

Synthesis and Crystal Structure of the Transition Metal Trimetaphosphimates Zn₃[(PO₂NH)₃]₂ · 14 H₂O and Co₃[(PO₂NH)₃]₂ · 14 H₂O The transition metal trimetaphosphimates Zn₃[(PO₂NH)₃]₂ · 14 H₂O and Co₃[(PO₂NH)₃]₂ · 14 H₂O were obtained by the reaction of an aqueous solution of Na₃(PO₂NH)₃ · 4 H₂O with the respective metal nitrate or halide (molar ratio 1 : 4). The structure of Zn₃[(PO₂NH)₃]₂ · 14 H₂O was solved by single crystal X‐ray methods. The structure of isotypic Co₃[(PO₂NH)₃]₂ · 14 H₂O was refined from X‐ray powder diffraction data using the Rietveld method (Zn₃[(PO₂NH)₃]₂ · 14 H₂O ( 1 ): P 1, a = 743.7(2), b = 955.9(2), c = 980.1(2) pm, α = 102.70(3), β = 90.46(3), and γ = 100.12(3)°, Z = 1; Co₃[(PO₂NH)₃]₂ · 14 H₂O ( 2 ): P 1, a = 746.05(1), b = 957.06(2), c = 988.51(2) pm, α = 102.162(1), β = 90.044(1), and γ = 99.258(1)°, Z = 1). In 1 and 2 the P₃N₃ rings of the trimetaphosphimate ions attain a conformation which can be described as a combination of an ideal boat and an ideal twist conformation. The trimetaphosphimate ions act as bridging ligands. Thus chains of alternating M²⁺ and (PO₂NH)₃^3– ions are formed which are interconnected by additional M²⁺ ions forming electro‐neutral double chains. In the solid these double chains are connected by hydrogen bonds.     

Isotherme à 25°C du Système Quaternaire Réciproque H3PO4?K2SO4?H2SO4?K3PO4?H2O Etude des Nappes du Liquidus

25°C Isotherm of the Reciprocal Quaternary System H₃PO₄? K₂SO₄? H₂SO₄? K₃PO₄? H₂O Study of the Liquidus Curves The liquidus of the reciprocal system H₃PO₄? K₂SO₄? H₂SO₄? K₃PO₄–H₂O has been investigated as a last step in the determination of the equilibrium diagram at 25°C and 1 atm pressure. Solubility has been detected by conductometric measurements in isopletic sections selected in order to complete the data obtained from the limiting ternary systems and the previously found boundary curves. Four isopletic sections have been completely established: K₂SO₄? KH₂PO₄, K₂SO₄? K₂HPO₄, KHSO₄? K₂HPO₄ and KHSO₄? KH₂PO₄. The two first ones are quasi ternary systems. Nine portions have been studied and the curves of equal water content plotted. The liquidus of KHSO₄, K₈(H₂PO₄)_1+x(HSO₄)_7?x and KH₂PO₄ · KHSO₄, show a rotationel shape which reveals a retrosolubility depending on the water content.     

Einfluss von H‐Brückenbindungen auf die Jahn–Teller‐Verzerrung in den Kettenstrukturen von 2,2′‐bipyMn(H2PO4)F2·H2O und 2,2′‐bipyMn(H2PO4)2F

In the system 2,2′‐bipyridine/Mn^III/HF/H₃PO₄/H₂O two compounds with chain structures could be prepared and characterised by X‐ray structure analyses. 2,2′‐bipyMn(H₂PO₄)F₂·H₂O ( 1 ): monoclinic, twinned, space group P2₁/c, Z = 4, a = 6.7883(4), b = 10.9147(5), c = 17.8102(8) Å, β = 100.142(4)°, R = 0.0328. 2,2′‐bipyMn(H₂PO₄)₂F ( 2 ): triclinic, space group P , Z = 2, a = 6.675(1), b = 10.715(1), c = 11.013(1) Å, α = 107.595(9)°, β = 90.994(9)°, γ = 95.784(8)°, R = 0.0252. Both compounds show chain structures with trans‐bridging dihydrogenphosphate ligands and bipy and two fluorine ligands for ( 1 ), or bipy, fluorine and an additional dihydrogenphosphate, respectively, for ( 2 ) in equatorial positions. Due to the pseudo‐Jahn–Teller effect, Mn^III shows elongated octahedral coordination with ferrodistortive ordering along the chain direction. The distortion is remarkably higher in ( 1 ) than in ( 2 ). This is discussed in context with additional hydrogen bonds along the chain in ( 2 ).     

Influence of silicic acid and glauconite on thermal dehydration of Ca(H2PO4)2 · H2O

The thermal dehydration of mixtures of Ca(H₂PO₄)₂·H₂O with silicic acid and glauconite was studied by thermal (under dynamic and quasi-isothermal-quasi-isobaric conditions), X-ray and Chromatographic analyses.It was found that the dehydration of Ca(H₂PO₄)₂·H₂O is accelerated in the mixtures. SiO₂·nH₂O and glauconite react with the intermediates of dehydration of Ca(H₂PO₄)₂·H₂O, and silicophosphates and Al, K, Fe-phosphates are formed, respectively. The total degree of polymerization of calcium polyphosphates is lower in the mixtures than in Ca(PO₃)₂ itself.

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Zusammenfassung Mittels röntgenographischer, chromatographischer und thermischer (unter dynamischen und quasi-isothermen-quasi-isobaren Bedingungen) Analyse wurde die thermische Dehydratation eines Gemisches aus Ca(H₂PO₄)₂·H₂O, KieselsÄure und Glaukonit untersucht.Es wurde festgestellt, da\ die Dehydratation von Ca(H₂PO₄)₂·H₂O im Gemisch beschleunigt ablÄuft. SiO₂·nH₂O und Glaukonit reagieren mit den Zwischenprodukten der Dehydratation von Ca(H₂PO₄)₂·H₂O und formen Silikophosphate und Al,K,Fe-Phosphate. Der totale Polymerisationsgrad von Calciumpolyphosphat ist im Gemisch geringer als in Ca(PO₃)₂ selbst.

     

Preparation and Crystal Structure of Sodium Iron Hydrogen Phosphate,NaFe(HPO4)(H2PO4)2 · H2O

Single crystals of sodium iron hydrogen phosphate, NaFe(HPO₄)(H₂PO₄)₂ · H₂O, were prepared hydrothermally by heating a mixture of Fe₂O₃, H₃PO₄ and Na₂CO₃ with a small amount of water. It crystallizes orthorhombic (Pbcn (N° 60), Z = 8, a = 872.91(7), b = 1249.54(8), c = 1894.4(1) pm). The crystal structure was solved by using 1121 unique reflections I > 2σ(I) and refined for a final conventional residual R = 0.039 (188 variables, 25 atoms including hydrogen in the asymmetric unit). The main feature of the crystal structure is a ReO₃-like network formed by hydrogenphosphate-, dihydrogenphosphate-groups and Fe O₆ octahedra with channels along the [201], [010] and [201] directions. Na⁺ and H₂O molecules are occupying these channels. Effective Coordination Numbers (ECoN), Mean Fictive Ionic Radii (MEFIR) and the Madelung Part of Lattice Energy (MAPLE) are calculated for the title compound.     

Etude de la deshydratation de Ca(H2PO4)2·H2O et de sa reaction avec CaSO4 par ATD-ATG couplees

The dehydration of Ca(H₂PO₄)₂·H₂O was examined with simultaneous DTA and TG. This dehydration permitted clearly the apparation of the following phases: Ca(H₂PO₄)₂·0.5H₂O, Ca(H₂PO₄)₂, Ca₃(HP₂O₇)₂, Ca₂HP₃O₁₀ et Ca(PO₃)₂. The reaction of Ca(H₂PO₄)₂·H₂O and CaSO₄ was also examined with the same technics. It was found that the decomposition of CaSO₄ takes place for relatively low temperature (between 600°C and 800°C).     

Synthesis and Crystal Structure of Lithium Tetrametaphosphimate Tetrahydrate Li4(PO2NH)4 · 4 H2O

Single crystals of Li₄(PO₂NH)₄ · 4 H₂O were obtained by dissolving LiOH and H₄(PO₂NH)₄ · 2 H₂O in water and subsequent precipitation with acetone and ethanol followed by slow evaporation of the solvents. The structure of Li₄(PO₂NH)₄ · 4 H₂O was solved by single‐crystal X‐ray methods ( (No. 2), a = 489.2(2), b = 853.2(2), c = 880.5(2) pm, α = 101.71(3), β = 102.39(3), γ = 94.88(3)°, Z = 1). The structure is composed of LiO₄ tetrahedra and (PO₂NH)₄^4? ions. The P₄N₄ rings of the anions exhibit a slightly distorted chair–1 conformation, which is supported by IR data and has been described by torsion angles, displacement asymmetry parameters and puckering parameters. Via Li⁺ ions and hydrogen bonds, the tetrametaphosphimate anions are connected forming a three‐dimensional network.     

3-D phase diagram of HPC/H2O/H3PO4 tertiary system

A 3-D phase diagram of the HPC/H₂O/H₃PO₄ tertiary system against various temperatures was established. Four distinct phases—the completely separated phase (S), the cloudy suspension phase (CS), the liquid crystalline miscible phase (LC), and the isotropically miscible phase (I)—were identified. The S phase shrank as the temperature increased, revealing that the HPC solubility increased with temperature, regardless of the LCST (lower critical solution temperature) characteristic. The addition of H₃PO₄ suppressed the formation of LC phase. However, as the temperature was raised sharply from 50 to 70?°C, the LC phase could only be maintained at high H₃PO₄ concentration region; it was a triangular shape, and the top apex of the triangle was the temperature-invariant L* point (HPC/H₂O/H₃PO₄ 38/9/53?wt%). The CS phase expanded considerably into the H₂O-rich but H₃PO₄-poor region when the temperature continued to increase over 48?°C. The LCST points of the CS phase that contained 0 and 15?wt% of H₃PO₄ were 34 and 38?°C, respectively. These CS results demonstrate that H₃PO₄ suppresses the occurrence of LCST behavior. Additionally, the binodal curve exhibits a weak or even zero dependence of binodal temperature on the HPC concentration at HPC concentrations of less than 30?wt% in a pure water system. A hypothesis concerning the sequential desorption of water molecules was proposed to explain such behavior.     

Polymorphism of [Zn(2,2′‐bipy)(H2PO4)2]2

Two polymorphs of a zero‐dimensional (molecular) zinc phosphate with the formula [Zn(2,2′‐bipy)(H₂PO₄)₂]₂ have been synthesized by a mild hydrothermal route and their crystal structures were determined by single crystal X‐ray diffraction (triclinic, space group (No. 2), Z = 2, α‐form: a = 8.664(1), b = 8.849(2), c = 10.113(2) Å, α = 97.37(2)°, β = 100.54(2)°, γ = 100.98(2)°, V = 737.5(3) ų; β‐form: a = 7.5446(15), b = 10.450(2), c = 10.750(2) Å, α = 67.32(3)°, β = 81.67(3)°, γ = 69.29(3)°, V = 731.4(3) ų). Both structures consist of distorted trigonal‐bipyramidal ZnO₃N₂ units condensed with PO₂(OH)₂ tetrahedra through common vertices giving rise to dimers [Zn(2,2′‐bipy)(H₂PO₄)₂]₂. The structures are stabilized by extensive inter‐ and intramolecular hydrogen bond interactions. Both modifications display subtle differences in their packing originating from the hydrogen bond interactions as well as π…π interactions between the organic ligands.     

Two new open framework cobalt phosphates: NaCo3(OH)(PO4)2.1/4H2O and Na(NH4)Co2(PO4)2.H2O

Two new cobalt phosphates, NaCo₃(OH)(PO₄)₂.1/4H₂O (1) and Na(NH₄)Co₂(PO₄)₂.H₂O (2) have been synthesized hydrothermally and characterized by single crystal X-ray diffraction methods, vibrational (IR and Raman) spectroscopy, thermogravimetric analysis and magnetic measurements. The structure of 1 is a new framework type while 2 is an example of a chiral cobalt phosphate. Both phases contain channels in which the Na⁺, NH₄⁺ cations and H₂O molecules are located.     

(C2H10N2)[BPO4F2] — Structural Relations between [BPO4F2]2— and [Si2O6]4—

(C₂H₁₀N₂)[BPO₄F₂] — Strukturbeziehungen zwischen [BPO₄F₂]^2— und [Si₂O₆]^4— Colourless crystals of (C₂H₁₀N₂)[BPO₄F₂] were prepared from mixture of ethylendiamine, H₃BO₃, BF₃ · C₂H₅NH₂, H₃PO₄ and HCl under mild hydrothermal conditions (220 °C). The crystal structure was determined by single crystal methods (triclinic, P1¯ (no. 2), a = 451.85(5) pm, b = 710.20(8) pm, c = 1210.2(2) pm, α = 86.08(1)°, β = 88.52(2)°, γ = 71.74(1)°, Z = 2) and contains infinite tetrahedral zweier‐single‐chains {[BPO₄F₂]^2—} which are isoelectronic (48e^—) with the polyanions {[Si₂O₆]^4—} of the pyroxene family.     

Kristallographische Orientierungsbeziehungen zwischen den Phasen der Reaktionsfolge Ca2[P4O12] · 4 H2O → β-(Ca2[PO3]4)x

Crystallographic Orientation Relations between the Phases in the Reaction Ca₂[P₄O₁₂] · 4 H₂O → β-(Ca₂[PO₃]₄)_x The dehydration of Ca₂[P₄O₁₂] · 4 H₂O modification I proceeds over several intermediate phases to β-(Ca₂[PO₃]₄)_x crystallographically oriented. One of the intermediate phases is X-ray amorphous. It is of special interest, that this amorphous phase does not interrupt the oriented course of the reaction. The β-polyphosphate transforms to β-Ca₂[P₂O₇] connected with the loss of P₂O₅ at further heating. The crystallographic orientation relations between educt and product were determined for all steps of the reaction. The unit cells of the phases were determined too.     

Synthesis,structure and NMR characterization of a new monomeric aluminophosphate [dl-Co(en)3]2[Al(HPO4)2(H1.5PO4)2(H2PO4)2](H3PO4)4 containing four different types of monophosphates

A new zero-dimensional (0D) aluminophosphate monomer [dl-Co(en)₃]₂[Al(HPO₄)₂(H_1.5PO₄)₂(H₂PO₄)₂](H₃PO₄)₄ (designated AlPO-CJ38) with Al/P ratio of 1/6 has been solvothermally prepared by using racemic cobalt complex dl-Co(en)₃Cl₃ as the template. The Al atom is octahedrally linked to six P atoms via bridging oxygen atoms, forming a unique [Al(HPO₄)₂(H_1.5PO₄)₂(H₂PO₄)₂]^6? monomer. Notably, there exists intramolecular symmetrical O?H?O bonds, which results in pseudo-4-rings stabilized by the strong H-bonding interactions. The structure is also featured by the existence of four different types of monophosphates that have been confirmed by ³¹P NMR and ¹H NMR spectra. The crystal data are as follows: AlPO-CJ38, [dl-Co(en)₃]₂[Al(HPO₄)₂(H_1.5PO₄)₂(H₂PO₄)₂](H₃PO₄)₄, M = 1476.33, monoclinic, C2/c (No. 15), a = 36.028(7) Å, b = 8.9877(18) Å, c = 16.006(3) Å, β = 100.68(3)°, U = 5093.2(18) Å³_, Z = 4, R₁ = 0.0509 (I > 2σ(I)) and wR₂ = 0.1074 (all data). CCDC number 689491.     

The bivalent metal hypophosphites Sr(H2PO2)2, Pb(H2PO2)2 and Ba(H2PO2)2

The structures of isomorphous monoclinic strontium and lead bis­(di­hydrogenphosphate), Sr(H₂PO₂)₂ and Pb(H₂PO₂)₂, and orthorhombic barium bis­(di­hydrogen­phos­phate), Ba(H₂PO₂)₂, consist of layers of hypophosphite anions and metal cations exhibiting square antiprismatic coordination by O atoms. The Sr and Pb atoms are located on sites with point symmetry 2, and the Ba atoms are on sites with point symmetry 222. Within the layers, each anion bridges four metal cations.