AgCo3PO4(HPO4)2

The structure of the hydro­thermally synthesized compound AgCo₃PO₄(HPO₄)₂, silver tricobalt phosphate bis­(hydrogen phosphate), consists of edge‐sharing CoO₆ chains linked together by the phosphate groups and hydrogen bonds. The three‐dimensional framework delimits two types of tunnels which accommodate Ag⁺ cations and OH groups. The title compound is isostructural with the compounds AM₃H₂(XO₄)₃ (A = Na or Ag, M = Co or Mn, and X = P or As) of the alluaudite structure type.     

Fe6.67(PO4)5.35(HPO4)0.65 and Fe6.23(PO4)4.45(HPO4)1.55: two new mixed‐valence iron phosphates

Two new mixed‐valence iron phosphates, namely heptairon pentaphosphate hydrogen phosphate, Fe_6.67(PO₄)_5.35(HPO₄)_0.65, and heptairon tetraphosphate bis(hydrogen phosphate), Fe_6.23(PO₄)_4.45(HPO₄)_1.55, have been synthesized hydrothermally at 973 K and 0.1 GPa. The structures are similar to that of Fe^II₃Fe^III₄(PO₄)₆ and are characterized by infinite chains of Fe polyhedra parallel to the [101] direction. These chains are formed by the Fe1O₆ and Fe2O₆ octahedra, alternating with the Fe4O₅ distorted pentagonal bipyramids, according to the stacking sequence ...Fe1–Fe1–Fe4–Fe2–Fe2.... The Fe3O₆ octahedra and PO₄ tetrahedra connect the chains together. Fe^II is localized on the Fe3 and Fe4 sites, whereas Fe^III is found in the Fe1 and Fe2 sites, according to bond‐valence calculations. Refined site occupancies indicate the presence of vacancies on the Fe4 site, explained by the substitution mechanism Fe^II + 2(PO₄³⁻) = vacancies + 2(HPO₄²⁻).     

Two caesium vanadium hydrogenphosphates with tunnelled structures: Cs2V2O3(PO4)(HPO4) and Cs2[(VO)3(HPO4)4(H2O)]·H2O

Dicaesium divanadium trioxide phosphate hydrogenphosphate, Cs₂V₂O₃(PO₄)(HPO₄), (I), and dicaesium tris[oxidovanadate(IV)] hydrogenphosphate dihydrate, Cs₂[(VO)₃(HPO₄)₄(H₂O)]·H₂O, (II), crystallize in the monoclinic system with all atoms in general positions. The structures of the two compounds are built up from VO₆ octahedra and PO₄ tetrahedra. In (I), infinite chains of corner‐sharing VO₆ octahedra are connected to V₂O₁₀ dimers by phosphate and hydrogenphosphate groups, while in (II) three vanadium octahedra share vertices leading to V₃O₁₅(H₂O) trimers separated by hydrogenphosphate groups. Both structures show three‐dimensional frameworks with tunnels in which Cs⁺ cations are located.     

A novel chain-like molybdenum phosphate: hydrothermal synthesis,crystal structure and characterization of [NH3(CH2CH2)2NH3]3[NH3(CH2CH2)2NH2]-Na5[Mo6O12(OH)3(PO4)(HPO4)3]2·4H2O

A novel organic/inorganic hybrid molybdenum phosphate, [NH₃(CH₂CH₂)₂NH₃]₃[NH₃(CH₂CH₂)₂NH₂]Na₅-[Mo₆O₁₂(OH)₃(PO₄)(HPO₄)₃]₂·4H₂O (1), involving molybdenum presented in V oxidation, has been hydrothermally prepared and characterized by elemental analysis, i.r., u.v.–vis., x.p.s., t.g. and single crystal X-ray diffraction. The structure of the title compound (1) may be considered to consist of two [Mo₆O₁₂(OH)₃(PO₄)(HPO₄)₃] units bonded together with NaO₆ octahedra, forming dimers. Further, these dimers connect with each other through four Na⁺ cations as bridges, giving rise to novel one-dimensional chain-like skeleton. Piperazines exist among inorganic chains acting as charge balancing cations.     

Doppelkettenstruktur von (pipzH2)[MnF2(HPO4)(H2O)](H2PO4)

By adding piperazine to a hydrofluoric and phosphoric acid solution of Manganese(III) fluoride, the fluoride phosphate (pipzH₂)[MnF₂(HPO₄)(H₂O)](H₂PO₄) can be crystallized. Its structure is built by piperazinium(2+) cations, (H₂PO₄)^? anions, and an anionic double‐chain of [HPO₄] tetrahedra and [MnO₃F₂(H₂O)] octahedra. The structure is triclinic, space group P , Z = 2, a = 622.97(4), b = 923.46(6), c = 1183.62(7) pm, α = 98.343(6)°, β = 100.747(7)°, γ = 107.642(5)°, R = 0.0289. It is worth noting that a ferrodistortive Jahn‐Teller order is observed with [MnO₃F₂(H₂O)] octahedra strongly elongated along the F–Mn–OH₂ axes perpendicular to the chain plane. The structure is stabilized by very strong hydrogen bonds.     

Synthesis and crystal structure of two fluorophosphated compounds with different infinite sheets: Sr2Ga(HPO4)(PO4)F2 and Sr2Fe2(HPO4)(PO4)2F2

New compounds, Sr₂Ga(HPO₄)(PO₄)F₂ and Sr₂Fe₂(HPO₄)(PO₄)₂F₂, have been prepared by hydrothermal synthesis (700°C, 180 MPa, 24 h) and characterized by single-crystal X-ray diffraction. Sr₂Ga(HPO₄)(PO₄)F₂ crystallizes in the monoclinic space group P2₁/n with a = 8.257(1) Å, b = 7.205(1) Å, c = 13.596(2) Å, β = 108.02(1)°, V = 769.2(2) ų and Z = 4 and Sr₂Fe₂(HPO₄)(PO₄)₂F₂ in the triclinic space group P2₁/n with a = 8.072(1) Å, b = 8.794(1) Å, c = 8.885(1) Å, α = 102.46(1)°, β = 115.95(1)°, γ = 89.95(1)°, V = 550.6(1) ų and Z = 2. Structures are both based on different sheets involving corner-linkage between octahedra and tetrahedra. The sheets are linked by Sr²⁺ cations. Structural relationships exist between the descloizite mineral and the title compounds.     

Barium vanadium(III) hydrogen ­phosphate,Ba3V2(HPO4)6

Hydro­thermally prepared Ba₃V₂(HPO₄)₆ contains a three‐dimensional network of V^IIIO₆ octahedra [d_av(V—O) = 2.014 (2) Å] and HPO₄ [d_av(P—O) = 1.537 (3) Å] tetrahedra, sharing vertices. 12‐coordinate Ba²⁺ cations [d_av(Ba—O) = 2.944 (4) Å] complete the structure.     

Potassium gallium hydrogenphosphate fluoride,K2Ga[H(HPO4)2]F2

Hydrothermally synthesized dipotassium gallium {hydrogen bis[hydrogenphosphate(V)]} difluoride, K₂Ga[H(HPO₄)₂]F₂, is isotypic with K₂Fe[H(HPO₄)₂]F₂. The main features of the structure are ([Ga{H(HPO₄)₂}F₂]²⁻)_n columns consisting of centrosymmetric Ga(F₂O₄) octahedra [average Ga—O = 1.966 (3) Å and Ga—F = 1.9076 (6) Å] stacked above two HPO₄ tetrahedra [average P—O = 1.54 (2) Å] sharing two O‐atom vertices. The charge‐balancing seven‐coordinate K⁺ cations [average K—O,F = 2.76 (2) Å] lie in the intercolumn space, stabilizing a three‐dimensional structure. Strong [O...O = 2.4184 (11) Å] and medium [O...F = 2.6151 (10) Å] hydrogen bonds further reinforce the connections between adjacent columns.     

One-step mild hydrothermal method to prepare low valent sodium vanadium(III) monohydrogenphosphate: NaV(HPO4)2

Green colored single crystals of a reduced sodium vanadium(III) monohydrogenphosphate, NaV(HPO₄)₂, were grown using a one-step mild hydrothermal method. The in situ reduction of V⁵⁺ to V³⁺ was performed using copper acetate as the reducing agent. The title compound crystalizes in the monoclinic space group Cc and exhibits a three-dimensional crystal structure that consists of distorted VO₆ octahedra connected to PO₃(OH) tetrahedra that are further connected via Na cations. The compound exhibits simple paramagnetic behavior at high temperatures and a discontinuity near 5 K is likely due to the onset of magnetic coupling. The compound was also characterized by TGA, IR and UV–vis spectroscopies.     

A new layered zinc phosphate templated by protonated isonicotinate, [Zn2(C6H5NO2)2(HPO4)2]

An organic–inorganic hybrid compound, poly­[bis­[(pyridine‐4‐carboxyl­ato)­zinc(II)]‐di‐μ₃‐phosphato], [Zn₂(C₆H₅NO₂)₂(HPO₄)₂], has been hydro­thermally synthesized and structurally characterized. The crystal structure consists of two types of two‐dimensional layers of zinc hydrogenphosphate templated by protonated isonicotinate (ina) (or 4‐pyridine­carboxylic acid), which contain two crystallographically independent centrosymmetric [Zn₂(ina)₂(HPO4)₂] dimers as basic building units. The layers are interconnected via hydrogen‐bonding and heterocyclic ring interactions.     

Dipotassium trimanganese(II) tetrakis(hydrogenphosphite), K2[Mn3(HPO3)4]

The title compound is a new mixed alkali/3d metal phosphite. It exhibits a layered structure formed by linear Mn₃O₁₂ trimer units which contain face‐sharing MnO₆ octahedra interconnected by (HPO₃)²⁻ phosphite oxoanions. The K⁺ cations located between the anionic [Mn₃(HPO₃)₄]²⁻ sheets are ninefold coordinated. The presence of the alkaline ion leads to the highest symmetry and shortest interlayer distance compared with two previous compounds showing the same anionic framework and having ammonium salts as cations. The compound crystallizes in the space group Rm, with two crystallographically independent Mn atoms occupying sites of m and 3m symmetry. All the other atoms, except for the phosphite O atoms, are located on special positions with 3m symmetry.     

Synthesis and Crystal Structure of KSc(HPO4)2

KSc(HPO₄)₂ was obtained by hydrothermal synthesis. The crystal structure was determined from single‐crystal X‐ray data: orthorhombic, space group Pnma (No. 62), a = 14.5095(10), b = 5.4260(4), c = 8.4882(5) Å, V = 668.26(8) ų and Z = 4. The crystal structure of KSc(HPO₄)₂ represents a new structure type containing twelve‐ and four‐membered rings forming channels along [010] built of alternating ScO₆ octahedra and HPO₄^2? groups. Potassium ions reside within the twelve membered ring channels.     

Hydrothermal Synthesis of a New Vanadium Tellurate(VI) with a Novel Chain Structure: (NH4)4{(VO2)2[Te2O8(OH)2]}·2H2O

A new ammonium vanadium tellurate, (NH₄)₄{(VO₂)₂[Te₂O₈(OH)₂]}·2H₂O ( 1 ) was hydrothermally synthesized and characterized by elemental analyses, IR spectrum, TG analysis, and single crystal X–ray diffraction. Compound 1 crystallizes in the monoclinic system, space group P2₁/n, a = 7.3843(15) Å, b = 17.111(3) Å, c = 7.3916(15) Å, β = 118.88(3)°, V = 817.9(3) ų, Z = 2, R1 (I>2σ(I)) = 0.0235, wR2 (all data) = 0.0462. The structure of 1 consists of infinite anionic chains, {(VO₂)₂[Te₂O₈(OH)₂]}^4? which contain octahedral VO₆ and TeO₅OH units. Each octahedral VO₆ and TeO₅OH unit is connected by sharing an edge to form V₂O₁₀ and Te₂O₈(OH)₂ binuclear units. The V₂O₁₀ and Te₂O₈(OH)₂ binuclear units are alternatively connected to one another, creating complete infinite {(VO₂)₂[Te₂O₈(OH)₂]}^4? chains along the c direction. The anionic chains are separated by ammonium cations and water molecules that link the chains through a network of hydrogen bonds. In addition, the structure contains an extended network of O–H·····O hydrogen bonds between the chains.     

NaSc3[HPO3]2[HPO2(OH)]6: Synthesis,Crystal Structure,and Thermal Decomposition

NaSc₃[HPO₃]₂[HPO₂(OH)]₆ was prepared by use of a phosphorus acid flux route. The crystal structure was determined from single‐crystal X‐ray diffraction data: triclinic, space group P$\bar{1}$ (No. 2), a = 7.4507(11) Å, b = 9.6253(17) Å, c = 9.6141(16) Å, α = 115.798(4)°, β = 101.395(4)°, γ = 101.136(3)°, V = 577.29(16) Å³ and Z = 1. The crystal structure of NaSc₃[HPO₃]₂[HPO₂(OH)]₆ contains two kinds of phosphate(III) groups: HPO₃^2– and HPO₂(OH)^–. Phosphate(III)‐tetrahedra, NaO₆ and ScO₆ octahedra together form a (3,6)‐connected net. During heating hydrogen and water are released and Sc[PO₃]₃ is formed as the main crystalline decomposition product.     

A hydrated ethyl­ene­di­ammonium salt of a new polymeric polyoxoanion: (H2en)4[Co(H2O)2(OH)2(VO)6(HPO4)4(PO4)4]·3H2O

The title compound, tetrakis­(ethyl­enedi­ammonium) tetra‐μ‐hydrogenphosphato‐di‐μ‐hydro­xo‐ tetra‐μ‐phosphato‐bis­(aqua­cobalt)­hexakis­(oxovanadium) trihydrate, was synthesized hydro­thermally at moderate temperature. The structure consists of diprotonated ethyl­enedi­ammonium cations and layers of the polyanions. The polyanion contains four PO₄ tetrahedra and three VO₅ square pyramids that are linked through corner‐sharing by alternating P—O—V, which gives rise to a chain. The chains, connected by CoO₄(H₂O)₂ octahedra, form layers, resulting in a two‐dimensional layered structure. The Co—O distances are in the range 1.984 (3)–2.038 (4) Å, the P—O distances 1.508 (3)–1.575 (3) Å and the V—O distances 1.585 (3)–2.010 (3) Å.     

Comparative study of two chemically isostructural polymers: [Cu2(VO2)(HPO4)2(NO3)(bpy)2]·2H2O/H3PO4 (bpy is 2,2′‐bi­pyridine)

The title compounds, poly­[bis(2,2′‐bi­pyridine)­bis(μ₃‐hydrogen phosphato)­nitratodi‐μ₂‐oxo‐dicopper(II)­vanadium dihydrate], [Cu₂(VO₂)(HPO₄)₂(NO₃)(C₁₀H₈N₂)₂]·2H₂O, (I), and poly­[bis(2,2′‐bi­pyridine)­bis(μ₃‐hydrogen phosphato)­nitratodi‐μ₂‐oxo‐dicopper(II)­vanadium phospho­ric acid solvate], [Cu₂(VO₂)(HPO₄)₂(NO₃)(C₁₀H₈N₂)₂]·H₃PO₄, (II), were obtained by similar hydro­thermal methods but under different crystallization conditions. The trinuclear entity which serves as the basic unit in both structures presents two independent Cu^II ions immersed in similar square‐pyramidal N₂O₃ environments plus an octahedral VO₆ core and is organized into a one‐dimensional polymer, which is essentially identical in the two structures. The compounds are stabilized by different solvates, viz. two crystallization water mol­ecules in (I) and a phospho­ric acid mol­ecule in (II), which provide the main structural differences through the diversity of interchain interactions in which they serve as bridges.     

Structure and spectral characteristics of (NH4)2[Re2(HPO4)4 · 2H2O]

The compound (NH₄)₂[Re₂(HPO₄)₄ · 2H₂O] has been synthesized and characterized by electronic and vibrational spectroscopy. The molecular structure has been determined by X-ray diffraction (MoK _α radiation, λ = 0.71073 Å). The (NH₄)₂[Re₂(HPO₄)₄ · 2H₂O] coordination units form centrosymmetrical binuclear ordering with each metal atom being coordinated in a distorted octahedron incorporating one rhenium atom, one oxygen atom of the water molecule, and four phosphate oxygen atoms in the equatorial plane. The rhenium-rhenium bond length (2.2207 Å) corresponds to a quadruple bond between the atoms. The [Re₂(HPO₄)₄ · 2H₂O]^2- complex anions in the crystal are associated through strong hydrogen bonds formed by the phosphate O-H···O groups. The stability of dirhenium(III) tetra-μ-phosphates in aqueous solutions is considered.     

Oxyfluorinated compounds with an open structure XVI. Synthesis,structure determination and magnetic properties of Fe4F3(PO4)(HPO4)4(H2O)4(N2C3H12) [ULM-15]

Fe₄F₃(PO₄)(HPO₄)₄(H₂O)₄(N₂C₃H₁₂) (labelled ULM-15) was prepared hydrothermally (7 days, 453 K, autogenous pressure) in the presence of 1,3-diaminopropane as organic template. Its structure was determined by single crystal X-ray diffraction. ULM-15 is monoclinic (Space group C2/c (no 15)) with lattice parameters a = 24.176(1) , b = 14.558(1) , c = 7.186(1) , β = 102.3(1)°, V = 2470.8(3) ³, Z = 4. Its three-dimensional framework is constituted from corner-sharing FeX₆ (X = O, F, H₂O) octahedra and tetrahedral PO₄ and HPO₄ groups. The structure presents trans-chains of FeO₄F₂ octahedra related to ferric dimers [Fe₂O₈F₂(H₂O)₂] by tetrahedral units. They delimit 16-membered rings channels along [001] in which the diprotonated amines are inserted. ULM-15 shows 3D antiferromagnetic behaviour below T_N ≈ 22 K.     

Synthesis, Characterization and Crystal Structure of a New Cobalt Phosphomolybdate that Contains [(Mo16O32)Co16(H2O)18(PO4)6(HPO4)18] Wheels

A new compound, [Co(H₂O)₆][{Co₂(H₂O)₆}{Co(H₂PO₄)₂}{(PO₄)₆(HPO₄)₁₈(Mo₁₆O₃₂)Co₁₆(H₂O)₁₈}] · 23H₂O (1), has been prepared under mild hydrothermal conditions and structurally characterized by elemental analyses, i.r. spectrum, XPS spectrum and single-crystal X-ray diffraction. Compound (1) consists of [(Mo₁₆O₃₂)Co₁₆- (H₂O)₁₈(PO₄)₆(HPO₄)₁₈] wheel-shape clusters as the structural motif, which are covalently linked by [Co₂(H₂O)₆] and [Co(H₂PO₄)₂] fragments to form a two-dimensional layer framework. It is the first time that such wheels have been linked by both mononuclear and dimeric Co^II octahedra. Electronic supplementary material Electronic supplementary material is available for this article at and accessible for authorised users.     

Hydrothermal Synthesis and Crystal Structure of CaIn2(PO4)2(HPO4): An octahedral-tetrahedral framework ternary calcium indium(III) phosphate

The new ternary calcium indium(III) phosphate CaIn₂(PO₄)₂(HPO₄) with mixed octahedral-tetrahedral framework was synthesized through hydrothermal reaction of stoichiometric amounts of CaO and InCl₃ with excess of H₃PO₄ and H₂O at pH = 1. Single crystal x-ray diffraction studies show the compound to crystallize in monoclinic symmetry, space group P2₁/n (#14) with a = 657.08(6), b = 2023.7(2), c = 665.72(7) pm, β = 91.20(1)°, Z = 4 and R = 0.043. The framework is built up of dimers of edge-sharing InO₆ octahedra forming In₂O₁₀ units sharing all their OXO ligands with PO₄ tetrahedra, and HPO₄ groups.