Kristallstrukturen von Verbindungen A2[MnF3(SO4)] (A = Rb,NH4, Cs): Jahn‐Teller‐Ordnung in Mangan(III)‐fluoridsulfaten. I.

Jahn‐Teller Ordering in Manganese(III) Fluoride Sulphates. I. Crystal Structures of A₂[MnF₃(SO₄)] (A = Rb, NH4, Cs) The three isostructural fluorosulphatomanganates(III) A₂[MnF₃(SO₄)] (A = Rb, NH₄, Cs) crystallize in space group P2₁/c, Z = 4. Rb₂[MnF₃(SO₄)]: a = 7.271, b = 11.091, c = 8.776Å, β = 92.26°, R = 0.033; (NH₄)₂[MnF₃(SO₄)]: a = 7.299, b = 10.157, c = 8.813Å, β = 91.51°, R = 0.025; Cs₂[MnF₃(SO₄)]: a = 7.365, b = 11.611, c = 9.211, β = 92.30°, R = 0.029. In the chain anions [MnF₃(SO₄)]^2— manganese(III) is coordinated by two trans‐terminal and two trans‐bridging fluorine ligands, and by the O‐atoms of two briding sulphate ligands in trans position. The Jahn‐Teller effect induces a variety of antiferrodistortive ordering resulting in distorted [MnF₄O₂] octahedra with alternating elongation of F—Mn—F — and O—Mn—O — axes, respectively. Thus, only asymmetrical bridges are formed.     

Ammonium and potassium fluoromonooxalatomanganates(II), A[MnF(C2O4)] (A = NH4 or K) and sodium fluoromonooxalatomanganate(II) dihydrate,Na[MnF(C2O4)] · 2H2O

Summary Light pink-white microcrystalline ammonium and potassium fluoromonooxalatomanganates(II), A[MnF(C₂O₄)] (A = NH₄ or K), and sodium fluoromonooxalatomanganate(II) dihydrate, Na[MnF(C₂O₄)] · 2H₂O, have been synthesized by two different methods. Either KMnO₄ is reduced in the presence of 40% HF and alkali metal oxalate, A₂C₂O₄ (A = NH₄, Na or K), or MnO(OH) in 40% HF reacts with A₂C₂O₄. Characterisation was made by elemental analyses, determination of oxidation states, magnetic susceptibility measurements and infrared spectral studies.     

Jahn‐Teller‐Ordnung in Mangan(III)‐fluoridsulfaten. II. Phasenübergang und Verzwillingung bei K2[MnF3(SO4)] und 1D Magnetismus in Verbindungen A2[MnF3(SO4)] (A = K,NH4, Rb,Cs)

Jahn‐Teller Ordering in Manganese(III) Fluoride Sulfates. II. Phase Transition and Twinning of K₂[MnF₃(SO₄)] and 1D Magnetism in Compounds A₂[MnF₃(SO₄)] (A = K, NH₄, Rb, Cs) According to single‐crystal X‐ray investigations, K₂[MnF₃(SO₄)] crystallizes at low temperature, like the isostructural Rb, NH₄, and Cs analogues in space group P2₁/c, Z = 4, e.g. at 100 K with a = 7.197, b = 10.704, c = 8.427Å, β = 91.84°. Below about 300 K, the crystals are found to be [001] axis twins. Using a new integration method for area detector records, nearly complete intensity data could be gained allowing for structure refinements of similar quality as for untwinned crystals (e.g. at 100 K: wR₂ = 0.050, R = 0.020 for all reflections). With rising temperature, the monoclinic angle approaches continuously 90°. For an ordering parameter Δβ = β?90° a 2^nd‐order phase transition is observed with an exponent λ = 0.17. At the transition temperature of 280 K resulting from the fit, the monoclinic structure changes – with delay – to orthorhombic with the minimum super‐group Pnca, a = 7.243, b = 10.763, c = 8.457Å, R = 0.024, as found in an early structure determination at room temperature by Edwards 1971. In the chain‐like [MnF₃(SO₄)]^2? anions, manganese(III) is octahedrally coordinated by two trans‐terminal and two trans‐bridging fluorine ligands as well as by the O atoms of two trans‐bridging sulfate ligands. At low temperature, the octahedral elongation by the Jahn‐Teller effect alternates between a F–Mn–F and an O–Mn–O axis (antiferrodistortive ordering). All bridges are asymmetric. From about 320 K on they become symmetric. Due to 2D dynamical Jahn‐Teller effect all octahedra appear compressed. All compounds A₂[MnF₃(SO₄)] show 1D antiferromagnetism. The antiferrodistortive Jahn‐Teller order at low temperatures and the small bridge angles explain the much lower magnetic exchange energies and their inverse relation to the bridge angles as compared with other fluoromanganate(III) chain compounds with the usual ferrodistortive ordering.     

Darstellung,Ramanspektren und Kristallstrukturen von V2O3(SO4)2, K[VO(SO4)2] und NH4[VO(SO4)2]

Preparation, Raman Spectra, and Crystal Structures of V₂O₃(SO₄)₂, K[VO(SO₄)₂], and NH₄[VO(SO₄)₂] The oxo-sulfato-vanadates(V) V₂O₃(SO₄)₂, K[VO(SO₄)₂], and NH₄[VO(SO₄)₂] have been prepared as crystals suitable for X-ray structure determination. In all structures sulfate acts as an unidentate ligand only toward a single vanadium atom. The structure of V₂O₃(SO₄)₂ consists of a threedimensional network of pairs of cornershared VO₆ octahedra with one terminal oxygen atom each, and SO₄ tetrahedra. All oxygen atoms of the sulfate ions are coordinated. NH₄[VO(SO₄)₂] and K[VO(SO₄)₂] are isostructural. VO₆ octahedra with one terminal oxygen atom and pairs of sulfate tetrahedra form infinite chains by corner sharing. The chains are weakly interlinked to layers. The sulfate ions are distorted towards planar SO₃ molecules and single oxygen atoms attached to vanadium. This structural detail gives an explanation for the mechanism of the reversible reaction K[VO(SO₄)₂] ? K[VO₂(SO₄)] + SO₃ at 400°C. Raman spectra of the compounds have been recorded and interpreted with respect to their structures. Crystal data: V₂O₃(SO₄)₂, monoclinic, space group P2₁/a, a = 947.2(4), b = 891.3(3), c? 989.1(4) pm, β = 104.56(3)°, Z = 4, 878 unique data, R(R_w) = 0.039(0,033); K[VO(SO₄)₂], orthorhombic, space group P2₁2₁2₁, a = 495.3(2), b = 869.6(9), c = 1 627(1)pm, Z = 4, 642 unique data, R(R_w) = 0,11(0,10); NH₄[VO(SO₄)₂], orthorhombic, space group P2₁2₁2₁, a = 495.3(1), b = 870.0(2), c = 1 676.7(4)pm, Z = 4, 768 unique data, R(R_w) = 0.088(0.083).     

Zur Struktur und Reaktivität des Diammoniumhexafluoromanganats(IV)

About the Structure and Reactivity of Diammonium Hexafluoromanganate(IV) Electrolytic oxidation of an aqueous suspension of MnF₂ containing NH₄F, and subsequent crystallization in 40% HF yields yellow crystals of (NH₄)₂MnF₆. It crystallizes in the hexagonal K₂MnF₆ type structure with the space group P6₃mc and a = 5.903; c = 9.565 Å; Z = 2. With in situ powder diffraction studies it is shown, that (NH₄)₂MnF₆ is gradually reduced in a NH₃ atmosphere between 30 and 230 °C to afford (NH₄)₃MnF₆, (NH₄)₂MnF₅, and finally NH₄MnF₃. (NH₄)₃MnF₆, thereby, forms a hitherto unknown cubic (a = 9.082 Å) high temperature modification with the cryolite type structure. Under N₂ the thermal decomposition of (NH₄)₂MnF₆ proceeds via NH₄MnF₄ to yield MnF₂.     

ASb2(SO4)2(PO4) (A = H3O+, K,Rb): Layered Structure Containing Ordered Sulfate and Phosphate Anions

Three compounds ASb₂(SO₄)₂(PO₄) (A = H₃O⁺, K, Rb) were obtained from the reactions of Sb₂O₃, A₂CO₃ (A = Li, Rb) or K₂SO₄ and NH₄H₂PO₄ in H₂SO₄ (98 %) at 220–250 °C. Their structures were determined by single‐crystal X‐ray diffraction. All compounds crystallize in the triclinic space group P$\bar{1}$ (no.2) and are isostructural. The crystal structures consist of two‐dimensional ²_∞[Sb₂(SO₄)₂(PO₄)]^– anionic layers and alkali cations, which are located between anionic layers. The anionic layers are composed of [SbO₄] ψ‐trigonal bipyramids, [SbO₅] ψ octahedra, [SO₄] tetrahedra, and [PO₄] tetrahedra. All compounds are characterized by solid state UV/Vis/NIR diffuse reflectance spectra, FT‐IR spectroscopy, and Raman spectroscopy.     

Topologisch und elektronisch bemerkenswerte „reduzierte”︁ Cluster des Typs [V18O42(X)]n− (X = SO4, VO4) mit Td-Symmetrie und davon abgeleitete Cluster [V(18–p)As2pO42(X)]m− (X = SO3, SO4, H2O; p = 3, 4)

Reduced Clusters with Remarkable Topological and Electronic Properties of the Type of [V₁₈O₄₂(X)]^n? (X = SO₄, VO₄) with T_d-Symmetry and Related Clusters [V_(18—p)As_2pO₄₂(X)]^m? (X = SO₃, SO₄, H₂O; p = 3, 4) The novel cluster-compounds Na₆[V₁₈O₄₂H₉(VO₄)] · 21 H₂O, (NH₄)₈[V₁₈O₄₂(SO₄)] · 25 H₂O, K₆[V₁₅As₆O₄₂(H₂O)] · 8 H₂O, (NH₄)₆[V₁₄As₈O₄₂(SO₃)], (NH₄)₆[V₁₄As₈O₄₂(SO₄)] and [N(CH3)₃]₄[₄V₁₄As₈0₄₂(H₂0)] were prepared and characterized by IR- and UV/Vis/NIR-spectroscopy, magnetic measurements and complete crystal structure analysis. For structural data see Inhaltsübersicht. Topological relations to the rhombicuboctahedron spanned by 24 0-atoms of the genuine hypothetical a-Keggin ion, at which the square planes are capped by V?O or As₂O groups, are discussed. Of particular interest are the ?extended”? Keggin ions [V₁₈O₄₂(X)]ⁿ- (X = SO₄ VO₄), (formaly derived from the hypothetical genuine a-Keggin ion by addition of six V?O groups) which have quite different electron populations in spite of the same structure of their cluster shells.     

Synthesis and Characterization of the Chain Borosulfates (NH4)3[B(SO4)3] and Sr[B2(SO4)4]

Two new borosulfates were obtained either by an open vessel synthesis from sulfuric acid and B(OH)₃, yielding (NH₄)₃[B(SO₄)₃] or from solvothermal synthesis in oleum enriched sulfuric acid and B(OH)₃, yielding Sr[B₂(SO₄)₄]. (NH₄)₃[B(SO₄)₃] crystallizes homeotypic to K₃[B(SO₄)₃] in space group Ibca (Z = 8, a = 728.58(3) pm, b = 1470.84(7) pm, c = 2270.52(11) pm), comprising open branched vierer single chains {¹_∞[B(SO₄)₂(SO₄)_2/2]^3–}. Sr[B₂(SO₄)₄] crystallizes as an ordered variant of Pb[B₂(SO₄)₄] in space group Pnna (Z = 4, a = 1257.4(4) pm, b = 1242.1(4) pm, c = 731.9(2) pm), consisting of loop branched vierer single chains {¹_∞[B(SO₄)_4/2]^2–}. Vibrational spectroscopy confirms both refined structure models. Thermal analysis of the dried powders, showed a decomposition towards the binary and ternary components, whereas a thermal treatment in the presence of the mother liquor promotes a decomposition of Sr[B₂(SO₄)₄] towards Sr[B₂O(SO₄)₃].     

Struktur und 1D‐magnetische Eigenschaften von (pipzH2)[MnF4(H2PO4)]

Structure and 1D‐magnetic properties of (pipzH₂)[MnF₄(H₂PO₄)] From hydrofluoric and phosphoric acid solution of Manganese(III), using piperazinium(2+) counter cations (pipzH₂²⁺) the chain‐anion [MnF₄(H₂PO₄)]^2— can be stabilized providing an interesting model system for studying the magnetic exchange interaction via phosphate bridges. Depending on the HF/H₃PO₄ excess (pipzH₂)[MnF₄(H₂PO₄)] crystallizes in two polymorphs I und II , differing mainly in the orientation of the cations. Form I is monoclinic, space group P2₁/c, Z = 4, a = 6.749(1), b = 12.039(1), c = 12.501(1) Å, β = 94.420(4)°, R = 0.023, Form II crystallizes in the same space group type P2₁/c, Z = 4, a = 6.651(1), b = 12.799(1), c = 12.825(1) Å, β = 110.312(5)°, R = 0.037. The Mn³⁺ ions are octahedrally surrounded by four terminal fluoride ligands and axially by bidentate bridging dihydrogenphosphate groups. The shape of the chain anions is very close in both modifications and characteristic for ferrodistortive Jahn‐Teller ordering.The Mn—O‐bonds along the chain direction are strongly elongated (distances 2.16 to 2.21 Å) whereas all Mn—F bond (1.81—1.88Å) are ruther short. On a large single crystal of form I 1D‐antiferromagnetic properties were found. By fitting an appropriate model based on the temperature dependence of the correlation lengths using an anisotropy constant D/k = —2.9 K a remarkably high exchange energy of J/k = —1.6(1) K along the chains could be determined.     

Ein Fluoridphosphat von Mangan(III) mit ungewöhnlicher Schichtstruktur: Na7[Mn5F13(PO4)3(H2O)3]

A Fluoride Phosphate of Manganese(III) with Unusual Layer Structure: Na₇[Mn₅F₁₃(PO₄)₃(H₂O)₃] The title compound was crystallized from a solution of MnF₃ · 3 H₂O in aqueous HF by addition of NaH₂PO₄ · H₂O in 2 M phosphoric acid. The crystal structure has been determined at 295 and 150 K on a trigonal crystal twinned by merohedry: Space group P3c1, Z = 4, a = 1055,0(1), c = 2314,0(1) pm (a = 1052,5(1), c = 2304,2(1) pm at 150 K), wR₂ = 0.0651 (0.0651). The structure contains anionic layers formed by triangular moieties of three [MnF₃O₂(H₂O)] octahedra sharing one common μ₃-F atom and bridged by three phosphate groups. Three of those groups, respectively, are interconnected by two [MnF₃O₃] octahedra over six phosphate O-atoms to form a trigonal layer in the a,b plane. Stacking of these layers gives channels along the c axis in which most of the Na⁺ ions are located. The [MnF₃O₂(H₂O)] octahedra show strong elongation along the μ₃-F–Mn–OH₂ axis mainly due to the Jahn-Teller effect whereas in the [MnF₃O₃] octahedra with C₃ symmetry weak signs only of a dynamical Jahn-Teller-effect can be observed. The magnetic properties (μ_eff = 4.61 μ_B, 3-D ordering point T_N = 3.3 K) were determined on powders and possible magnetic exchange pathways are discussed.     

The First Aqua Pentafluoro Manganates(III) – Syntheses and Structures

For the first time aqua pentafluoro manganate(III) compounds with different organic N-cations have been prepared and their crystal structures have been determined: N,N′-DMenH₂[MnF₅(H₂O)] · H₂O 1 (N,N′-DMen = N,N′-Dimethylethylenediamine), space group P2₁/c, a = 916.0, b = 1004.8, c = 1247.9 pm, β = 106.03°, R = 0.035; NMpipzH₂ · [MnF₅(H₂O)] · H₂O 2 (NMpipz = N-Methylpiperazine), space group P2₁/n, a = 757.7, b = 1261.9, c = 1197.1 pm, β = 105.09°, R = 0.027; N,N′-DMpipzH₂[MnF₅(H₂O)] · 2 HF 3 (N,N′-DMpipz = N,N′-Dimethylpiperazine), space group P1, a = 677.1, b = 863.9, c = 1187.7 pm, α = 79.18°, β = 81.63° γ = 67.62°, R = 0.026; and N,N-DMenH₂[MnF₅(H₂O)] · 1/2 HF 4 (N,N-DMen = N,N-Dimethylethylenediamine), space group P1, a = 859.3, b = 1086.5, c = 1092.0 pm, α = 86.96°, β = 78.52° γ = 89.01°, R = 0.035. In all compounds the [MnF₅(H₂O)]^2– octahedra are connected via H-bonds forming 3 D and 2 D network arrangements. The anions are strongly elongated by the Jahn-Teller effect. The FTIR spectra are presented.     

Synthesis and Structure of the First Three‐legged Low‐dimensional Iron Phosphate, [H3N(CH2)3NH2(CH2)2NH2(CH2)3NH3][Fe3F6(HPO4)2(PO4)]·3H2O

A hydrothermal reaction of iron acetylacetonate, phosphoric acid, HF, N, N′‐bis(3‐aminopropyl)ethylenediamine and water at 150 °C gave rise to a new iron phosphate, [H₃N(CH₂)₃NH₂(CH₂)₂NH₂(CH₂)₃NH₃][Fe₃F₆(HPO₄)₂(PO₄)] · 3H₂O ( I ). The structure consists of Fe(1)O₄F₂, Fe(2)O₃F₃ octahedral and P(1)O₃(OH) and P(2)O₄ tetrahedral building units connected through their vertices to form fragments of tancoite‐type units. The tancoite‐type units are linked through the phosphate tetrahedra forming an unusual iron phosphate with a hitherto unknown low‐dimensional structure with three‐iron center.Magnetic studies indicate a complex behavior at low temperature and the high‐temperature data (150 — 300 K) has a Curie‐Weiss behavior. The calculated room temperature magnetic moment is 6 μ_B per Fe atom, and the Neel temperature, T_N = 46K. Crystal data: orthorhombic, space group = I2₁2₁2₁ (no. 24), a = 9.9042(11), b = 12.8865(14), c = 19.783(2)Å, U = 2524.9(5), Z = 4.     

Kaliumhydrogensulfat-Dihydrogensulfat,K(HSO4)(H2SO4) – Synthese und Kristallstruktur

Potassium Hydrogensulfate Dihydrogensulfate, K(HSO₄)(H₂SO₄) – Synthesis and Crystal Structure Single crystals with the composition KH₃(SO₄)₂ have been synthesized from the system Potassium sulfate/sulfuric acid. The hitherto crystallographically not investigated compound crystallizes in the monoclinic space group P2₁/c (14) with the unit cell parameters a = 7.654(3), b = 11.473(5) and c = 8.643(3) Å, β = 112.43(3)°, V = 701.6 ų, Z = 4 and D_x = 2.22 g · cm^?3. The structure contains two types of tetrahedra, SO₃(OH) and SO₂(OH)₂. These tetrahedra form tetramers via hydrogen bonds consisting of both, two SO₃(OH) and two SO₂(OH)₂ tetrahedra. The tetramers are linked to each other via hydrogen bonds. Potassium is coordinated by 9 oxygen atoms which belong to both kinds of tetrahedra. These potassium oxygen polyhedra are connected by common faces forming chains running parallel z.     

Variation of 2 D Hydrogen Bond Topology in Diaqua-tetrafluoromanganates(III): 2-picoH[MnF4(H2O)2], TMEDAH2[MnF4(H2O)2]2, and TMBDAH2[MnF4(H2O)2]2

The crystal structures of three new diaqua-tetrafluoro-manganate(III) compounds with different organic N-cations have been determined: 2-picoH[MnF₄(H₂O)₂] 1 (2-pico = 2-methyl-pyridine), space group P2₁/c, a = 9.439, b = 13.662, c = 7.641 Å, β = 91.31°; R = 0.059; TMEDAH₂[MnF₄(H₂O)₂]₂ 2 (TMEDA = N,N,N′,N′-tetramethyl ethane diamine), space group P2₁/c, a = 5.421, b = 15.970, c = 9.677 Å, β = 96.37°, R = 0.031, and TMBDAH₂[MnF₄(H₂O)₂]₂ 3 (TMBDA = N,N,N′,N′-tetramethyl-1,4-butane-diamine), space group P2₁/n, a = 12.631, b = 5.577, c = 12.976 Å, β = 98.10°, R = 0.040. All three compounds show 2 D H-bonding networks of [MnF₄(H₂O)₂]^– anions separated by the organic cations. However, the topology of the anionic H-bonding nets is different for each compound. The anions are strongly elongated by the Jahn-Teller effect and are arranged in a ferrodistortive way in compounds 1 and 2 , whereas in compound 3 the arrangement is described as in a herringbone-like antiferrodistortive variant.     

Complex Carbonates of Iron(III)

The complex carbonates of iron(III) are shown to be anionic in nature. The solutions containing these complexes show a maximum absorbance at 460 nm. The complex carbonates of iron(III), viz., (i) K₆[Fe₂(OH)₂(CO₃)₅] · H₂O, — (ii) Na₂[Fe₃O₂(OH)₃(CO₃)₂], — (iii) K[Co(NH₃)₆]₂[Fe₃(OH)₄(CO₃)₆], — (iv) K₅[Co(NH₃)₆]₃[Fe₃(OH) ₄(CO₃)₆]₂, — (v) K[Co(NH₃)₆][Fe₂(OH)₄(CO₃)₃], and (vi) NH₄[Co(NH₃)₆][Fe₂(OH)₄(CO₃)₃] are isolated and studied by thermogravimetry. The infrared spectra of these compounds are recorded and probable band assignments made. Besides, the reaction between KHCO₃ and Fe(NO₃)₃ was studied through chemical and physicochemical methods.     

Kristallstruktur,Schwingungsspektren und Normalkoordinatenanalyse von K2[IrCl5(NH3)]

Crystal Structure, Vibrational Spectra, and Normal Coordinate Analysis of K₂[IrCl₅(NH₃)] The X-ray structure determination of K₂[IrCl₅(NH₃)] (orthorhombic, space group Pnma, a = 13.426(4), b = 10.015(2), c = 6.8717(7) Å, Z = 4) revealed the C_s point symmetry of the complex anion [IrCl₅(NH₃)]^2? (Ir? Cl = 2.337–2.365, Ir? N = 2.067(10); N? H = 0.73–0.79 Å). Using the molecular parameters the IR and Raman spectra are assigned by normal coordinate analysis. The valence force constants are f_d(NH) = 5.88, f_d(IrN) = 2.66, f_d(IrCl) = 1.68 mdyn/Å.     

Structural, vibrational and dielectric properties of the new mixed solution K0.84(NH4)1.16SO4Te(OH)6

Synthesis, crystal structure, DSC characterization, dielectric and Raman measurements are given for a new mixed solution K_0.84(NH₄)_1.16SO₄Te(OH)₆ (KNST). X-ray studies showed that the title compound crystallizes in the monoclinic system (P2₁/c) with the following parameters: , , , β=120.17(2)° and Z=4. The structure can be regarded as being built of isolated TeO₆ octahedra, SO₄ tetrahedra and cations. The main feature of this structure is the coexistence of two types of hydrogen bonds OHO and NHO ensuring the cohesion of the crystal. Crystals of K_0.84(NH₄)_1.16SO₄Te(OH)₆ undergo two endothermic peaks at 425 and 480 K and a shoulder at 470 K. These transitions detected by DSC and analyzed by dielectric measurements using the impedance and modulus spectroscopy techniques. Raman scattering measurements on K_0.84(NH₄)_1.16SO₄Te(OH)₆ material taken between 300 and 620 K are reported in this paper. The spectra indicate clearly two phase transitions.     

In situ Untersuchungen der Reaktion von Ammoniummonomolybdat, (NH4)2MoO4, mit Ammoniak: Die Struktur von (NH4)2[Mo3O10]

In situ Investigation of the Reaction of Ammonium Monomolybdate (NH₄)₂MoO₄ with Ammonia: The Structure of (NH₄)₂[Mo₃O₁₀] The reactivity of both polymorphs of (NH₄)₂MoO₄ with ammonia was investigated in a temperature range between 20 and 180 °C. Time and temperature controlled X‐ray powder diffraction as well as thermogravimetrical and differential thermal analysis were used to investigate this reaction.The formation of (NH₄)₂[Mo₃O₁₀] from (NH₄)₂MoO₄ is reversible in a humid and irreversible in a dry NH₃ gas flow. Heating (NH₄)₂MoO₄(mP60) under an atmosphere of humid NH₃ at about 170 °C forms (NH₄)₂[Mo₃O₁₀] and succesively cooling yields the (NH₄)₂MoO₄(mS60) polymorph. (NH₄)₂[Mo₃O₁₀] crystallises isostructural to the potassium compound with space group C2/c (No. 15) and lattice constants a = 1398.2(4), b = 804.1(2), b = 921.0(3) pm and β = 98.833(4)°.     

Novel K/Mn phosphate hydrates,K2Mn3(H2O)2[P2O7]2 and KMn(H2O)2[Al2(PO4)3]: hydrothermal synthesis and crystal chemistry

Two novel K/Mn phosphate hydrates, namely, dipotassium trimanganese dipyrophosphate dihydrate, K₂Mn₃(H₂O)₂[P₂O₇]₂, (I), and potassium manganese dialuminium triphosphate dihydrate, KMn(H₂O)₂[Al₂(PO₄)₃], (II), were obtained in the form of single crystals during a single hydrothermal synthesis experiment. Their crystal structures were studied by X‐ray diffraction. Both new compounds are members of the morphotropic series of phosphates with the following formulae: A₂M₃(H₂O)₂[P₂O₇]₂, where A = K, NH₄, Rb or Na and M = Mn, Fe, Co or Ni, and AM²⁺(H₂O)₂[M³⁺₂(PO₄)₃], where A = Cs, Rb, K, NH₄ or (H₃O); M²⁺ = Mn, Fe, Co or Ni; and M³⁺ = Al, Ga or Fe. A detailed crystal chemical analysis revealed correlations between the unit‐cell parameters of the members of the series, their structural features and the sizes of the cations. It has been shown that a mixed type anionic framework is formed in (II) by aluminophosphate [(AlO₂)₂(PO₄)₂]_∞ layers, with a cationic topology similar to the Si/Al‐topology of the crystal structures of feldspars. A study of the magnetic susceptibility of (II) demonstrates a paramagnetic behaviour of the compound.     

X‐Ray Crystal Structures of Hexa‐oxotellurate Complexes of Ruthenium(VI) and Silver(III): Na6[RuO2{TeO4(OH)2}2]·16H2O and Na5[Ag{TeO4(OH)2}2]·16H2O

X‐ray crystal structures are reported for Na₆[RuO₂{TeO₄(OH)₂}₂]·16H₂O and Na₅[Ag{TeO₄(OH)₂}₂]·16H₂O which contain respectively Ru^VI and Ag^III coordinated to chelating bidentate tellurate ([TeO₄(OH)₂]⁴⁻) groups. Na₆[RuO₂{TeO₄(OH)₂}₂]·16H₂O: Space group P1¯, Z = 2, lattice dimensions at 120 K; a = 6.9865(1), b = 8.7196(2), c = 11.7395(2)Å, α = 74.008(1), β = 79.954(1), γ = 88.514(1)°; R1 = 0.025. Na₅[Ag{TeO₄(OH)₂}₂]·16H₂O: Space group P1¯, Z = 2, lattice dimensions at 120 K; a = 5.888(1), b = 8.932(1), c = 12.561(2)Å, α = 98.219(6), β = 97.964(9), γ = 93.238(14)°; R1 = 0.047.