Sur L'Existence d'un Intermediaire Reactionnel Entre Phosphate et Pyrophosphate Acide de Potassium: Cas de K2H8(PO4)2P2O7

On the Existence of Intermediate Reaction Products of Potassium Hydrogen Phosphate and Diphosphate: K₂H₈(PO₄)₂P₂O₇ The crystal structure of K₂H₈(PO₄)₂P₂O₇ has been determined from diffractometer data obtained using MoKα radiation. The space group is Pca2₁ with a = 9.364(2), b = 7.458(2) and c = 19.560(2) Å, V = 1 366.0 ų; d_m = 2.17(1) g/cm³. Z = 4 · μ(MoKα) = 12.47 cm^?1. The structure was solved by direct methods. The crystal structure was refined to R = 0.025 for 416 independent reflexions. Two kinds of PO₄ exist and the mean value of P? O is 1.55(2) Å for one and 1.53(2) Å for the other. In P₂O₇ the angle P? O? P is 135(1)°. The distances P? O of bridge are 1.59(2) and 1.57(2) Å the mean value of P? O in terminals ? PO₃ is 1.51(2) Å. The coordination numbers of the potassium ions are nine and eight. K₂H₈(PO₄)₂P₂O₇, compound with mixed anion PO₄/P₂O₇ may be considered as reactional intermediary between acid orthophosphate and pyrophosphate.     

A new dinuclear molybdenum(V)-sulfur complex containing citrate ligand: Synthesis and characterization of K2.5Na2NH4[Mo2O2S2(cit)2].5H2O

The complex, K_2.5Na₂NH₄[Mo₂O₂S₂(cit)₂]·5H₂O (1), was obtained by crystallization from a solution of (NH₄)₂MoS₄, potassium citrate (K₃cit) and hydroxyl sodium in methanol and water under an atmosphere of pure nitrogen at ambient temperature. The crystals are triclinic, space group P1¯, a = 7.376 (3)Å, b = 14.620 (2) Å, c = 14.661 (1) Å, α = 71.10 (1)°, β = 81.77 (1)°, γ = 78.27(2)°, R = 0.0584 for 2545 observed (I > 2σ (I)) reflections. Single crystal structure analysis reveals that citrate ligand coordinated to molybdenum atom through two carboxylato oxygens and one deprotonated hydroxyl oxygen together with two bridging sulfur atoms and a terminal oxygen atom completes distorted coordination octahedron around each molybdenum atom. Principal dimensions are Mo = O₁, 1.707 Å (av); Mo-S_b, 2.341 Å (av); Mo-O_(hydroxyl), 2.021 Å (av); Mo-O_{(α-carboxyl)}, 2.1290 Å (av) and Mo-O_{(β-carboxyl)}, 2.268(av) Å. IR spectrum is in agreement with the structure.     

A series of Mixed-Valent Molybdenum Monophosphates,isotypic with leucophosphite represented by CsMo2P2O10 and K1.5Mo2P2O10 · H2O

The structure of two mixed valent molybdenum phosphates, CsMo₂P₂O₁₀ and K_1.5Mo₂P₂O₁₀ · H₂O has been solved from single crystals by X-ray diffraction in the space group P2₁/c with a = 9.428(1), b = 9.943(2), c = 12.348(2) Å and β = 127.38(1)° for CsMo₂P₂O₁₀ and a = 9.721(2), b = 9.805(3), c = 12.329(3) Å and β = 128.73(2)° for K_1.5Mo₂P₂O₁₀ · H₂O. These compounds isotypic with NH₄Mo₂P₂O₁₀ · H₂O and RbMo₂P₂O₁₀ · (1 ? x)H₂O exhibit the leucophosphite structure. The possibility of cationic non stoichiometry in this structure is also shown by the synthesis of two isotypic compounds A_1.5Mo₂P₂O₁₀ · xH₂O (A = Rb, Tl). In these monophosphates, one site Mo(1) is fully occupied by Mo^V, whereas the other octahedral site Mo(2) exhibits a variable valency Mo^III? Mo^IV to Mo^V. The main difference between these different phosphates deals with the distribution of the A cations inside the tunnels, depending upon their size and their content.     

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.     

Preparation and crystal data for two trimetaphosphate tellurates: Te(OH)6 · 2Na3P3O9 · 6H2O and Te(OH)6 · K3P3O9 · 2H2O

Te(OH)₆ · 2Na₃P₃O₉ · 6H₂O, is hexagonal (P6₃/m) with a = 11,67(1), c = 12,12(1) Å, Z = 2 and D_x = 2,225 g/cm³. Te(OH)₆ · K₃P₃O₉ · 2H₂O, is monoklin (P2₁/c) with a = 19,61(5), b = 7,456(1), c = 14,84(6) Å, = 108,01(4), Z = 4 and D_x = 2,506 g/cm³. Both compounds are the first examples of phosphate tellurates in which the anion phosphate is condensed to the ring anion P₃O₉. As in phosphate tellurates already described the phosphate groups are independent of the TeO₆ octahedra.     

Neue Oxocuprate (I). Über Cs3Cu5O4, Rb2KCu5O4, RbK2Cu5O4 und K3Cu5O4

New Oxocuprates(I). On Cs₃Cu₅O₄, Rb₂KCu₅O₄, RbK₂Cu₅O₄ and K₃Cu₅O₄ Cs₃Cu₅O₄ light yellow, powder as well as single crystals [a = 10.313(9), b = 7.630(1), c = 14.750(4) Å, β = 106.48(6)°], Rb₂KCu₅O₄ [a = 9.724(2), b = 7.443(0), c = 14.246(2) Å, β = 106.78(8)°], RbK₂Cu₅O₄ [a = 9.561(1), b = 7.411(0), c = 14.111(1) Å, β = 106.76(7)°] and K₃Cu₅O₄ [a = 9.422(1), b = 7.364(1), c = 13.995(2) Å, β = 107.00(2)°] are new prepared. The colour of the powders becomes lighter according to the sequence showed above. K₃Cu₅O₄ shows pale yellow. The Madelung Part of Lattice Energy, MAPLE, is calculated and discussed.     

New examples of mixed-ligand bis(hexafluoroacetylacenonato)copper(II) complexes with 3-imidazoline nitroxide radicals at a Cu(C5HF6O2)2∶L=3∶2 ratio (L2=C14H19N2O,L3=C13H17N2O3)

The crystal structures of two (hexafluoroacetylacetonato)copper(II) complexes with 3-imidazoline nitroxide radicals, [Cu(C₅HF₆O₂)₂]₃ (C₁₄H₁₉N₂O)₂ (I) and [Cu(C₅HF₆O₂)₂]₃ (C₁₃H₁₇N₂O₃)₂ (II), have been determined. The compounds are triclinic (PI, Z=1) with a=8.730(2), b=10.357(2), c=21.996(5) Å, α=103.24(2), β=94.03(2), γ=95.04(2)⁰, V=1920(1) ų for I and a=8.679(2), b=14.769(4), c=15.368(4) Å, α=85.58(2), β=96.25(1), γ=104.60(1)⁰, V=1893(1) ų for II. Complexes I and II are molecular. The trinuclear molecules are centrosymmetric relative to the Cu(1) atom. The coordination polyhedron of Cu(1) is a square bipyramid formed by the O atoms of the hfac anions and nitroxide radicals (average Cu?O_hfac 1.92(1) for I and 1.93(1) Å for II; Cu?O_N?O 2.47(1) for I and 2.56(1) Å for II). The coordination polyhedron of Cu(2) is a trigonal bipyramid formed by the O atoms of the hfac anions (Cu?O_hfac 1.91(1)–2.12(1) for I and 1.91(1)–2.09(1) Å for II) and an imine N atom of the radical (Cu(2)?N(2) 2.00(1) for I and 2.03(1) Å for II). The molecules are linked by van der Waals forces.     

Crystal Structures of Alkali Metal Peroxodiphosphates

Peroxodiphosphates of alkali metals can be prepared from K₄P₂O₈, which is synthesized by electrolysis, in metathesis reactions with the corresponding perchlorates. Single crystals have been obtained by diffusion of methanol into aqueous solutions of the peroxodiphosphates. The crystal structures of Li₄P₂O₈·4H₂O (P2₁/n; a = 8.057(2) Å, b = 5.074(1) Å, c = 12.288(3) Å, β = 100.53(2)°; V = 493.9(2) ų; Z = 2), Na₄P₂O₈·18H₂O (at 130 K: P6₁; a = 9.0984(14) Å, c = 49.926(13) Å; V = 3579.2(12) ų; Z = 6) and K₄P₂O₈ (P2₁/c; a = 5.9041(15) Å, b = 10.254(2) Å, c = 7.356(2) Å, β = 99.05(3)°; V = 439.79(18) ų; Z = 2) have been determined by X‐ray diffraction. In the Li salt the cations are tetrahedrally coordinated by one water molecule and three oxygen atoms of the anions, whereas the Na salt is characterized by binuclear [Na₂(H₂O)₉]²⁺ complexes. At low temperatures, the latter undergoes a phase transition from a structure with disordered anions to a completely ordered phase. K₄P₂O₈ is solvent‐free and exhibits irregular cation coordination. The structure of the peroxodiphosphate anion is very similar in all compounds; the mean O–O distance is 1.49(1) Å. In addition, the structure determination of K₄(HPO₄)₂·3H₂O₂ (P2₁/n; a = 6.076(1) Å, b = 6.579(1) Å, c = 17.215(2) Å, β = 99.73(1)°; V = 678.26(17) ų; Z = 2), which can be mistaken for K₄P₂O₈, is presented.     

Tripotassium tris­(oxalato‐κ2O,O′)­aluminate bis(hydrogen peroxide) hydrate,the first example of a cyclic hydrogen‐bonded H2O2 dimer

In addition to associating into cyclic hydrogen‐bonded dimers [O⋯O = 2.663 (1) and 2.914 (1) Å], each hydrogen peroxide mol­ecule in the title structure, K₃[Al(C₂O₄)₃]·1.75H₂O₂·0.25H₂O, hydrogen bonds to a neighbouring oxalate ligand [O⋯O = 2.700 (1) and 2.730 (1) Å] and coordinates to two K⁺ ions [K⋯O = 2.6620 (9)–2.8380 (7) Å].     

Über ein Kaliumoxonitridomonocyclowolframat(VI), K10[(WN2,5O0,5)4], mit Ringen aus vier eckenverknüpften Tetraedern (WX2X2/2)4 mit X = N,O

Potassium Oxo Nitrido Mono Cyclo Tungstate(VI), K₁₀[(WN_2.5O_0.5)₄] with Rings of Four Corner‐Sharing Tetrahedra (WX₂X_2/2)₄ with X = N, O Reactions of mixtures of potassium amide, tungsten powder and tungsten(VI) oxide in autoclaves at 650 °C lead to yellow potassium oxo nitrido mono cyclo tungstate (VI), K₁₀[(WN_2.5O_0.5)₄], which crystallizes isotypic to Ba₁₀[(TiN₃)₄]. After the reaction is finished, crystals are embedded in a matrix of potassium metal. They were isolated by washing out the metal with liquid ammonia. X‐ray investigations showed that K₁₀[(WN_2.5O_0.5)₄] crystallizes in the space group P1 with lattice parameters a = 6.569(5) Å, b = 9.437(2) Å, c = 9.559(3) Å, α = 106.20(2)°, β = 101.93(5)°, γ = 108.20(3)° and Z = 1. The crystal structure contains rings of four corner‐sharing tetrahedra (WX₂X_2/2)₄ with X = N, O which are packed along the a‐axis forming the motif of a hexagonal rod packing of columns. Potassium ions are located mainly between these columns but also within them.     

Crystal Structures of [Mn2(H2O)4(phen)2(C4H4O4)2] · 2 H2O and [Mn(phen)2(H2O)2][Mn(phen)2(C4H4O4)](C4H4O4) · 7 H2O

Reactions of 1,10‐phenanthroline monohydrate, Na₂C₄H₄O₄ · 6 H₂O and MnSO₄ · H₂O in CH₃OH/H₂O yielded a mixture of [Mn₂(H₂O)₄(phen)₂(C₄H₄O₄)₂] · 2 H₂O ( 1 ) and [Mn(phen)₂(H₂O)₂][Mn(phen)₂(C₄H₄O₄)](C₄H₄O₄) · 7 H₂O ( 2 ). The crystal structure of 1 (P1 (no. 2), a = 8.257(1) Å, b = 8.395(1) Å, c = 12.879(2) Å, α = 95.33(1)°, β = 104.56(1)°, γ = 106.76(1)°, V = 814.1(2) ų, Z = 1) consists of the dinuclear [Mn₂(H₂O)₄(phen)₂(C₄H₄O₄)₂] molecules and hydrogen bonded H₂O molecules. The centrosymmetric dinuclear molecules, in which the Mn atoms are octahedrally coordinated by two N atoms of one phen ligand and four O atoms from two H₂O molecules and two bis‐monodentate succinato ligands, are assembled via π‐π stacking interactions into 2 D supramolecular layers parallel to (101) (d(Mn–O) = 2.123–2.265 Å, d(Mn–N) = 2.307 Å). The crystal structure of 2 (P1 (no. 2), a = 14.289(2) Å, b = 15.182(2) Å, c = 15.913(2) Å, α = 67.108(7)°, β = 87.27(1)°, γ = 68.216(8)°, V = 2934.2(7) ų, Z = 2) is composed of the [Mn(phen)₂(H₂O)₂]²⁺ cations, [Mn(phen)₂(C₄H₄O₄)] complex molecules, (C₄H₄O₄)^2– anions, and H₂O molecules. The (C₄H₄O₄)^2– anions and H₂O molecules form 3 D hydrogen bonded network and the cations and complex molecules in the tunnels along [001] and [011], respectively, are assembled via the π‐π stacking interactions into 1 D supramolecular chains. The Mn atoms are octahedrally coordinated by four N atoms of two bidentate chelating phen ligands and two water O atoms or two carboxyl O atoms (d(Mn–O) = 2.088–2.129 Å, d(Mn–N) = 2.277–2.355 Å). Interestingly, the succinato ligands in the complex molecules assume gauche conformation bidentately to chelate the Mn atoms into seven‐membered rings.     

Crystal Structure and Thermal Behaviour of K2[CrF5·H2O]

K₂[CrF₅·H₂O] is monoclinic: a = 9.6835(3) Å, b = 7.7359(2) Å, c = 7.9564(3) Å, β = 95.94(1)°, Z = 4, space group C2/c (n^o 15). Its crystal structure was solved from its X‐ray powder pattern recorded on a powder diffractometer, using for the refinement the Rietveld method. It is built up from isolated octahedral [CrF₅·OH₂]^2? anions separated by potassium cations. The dehydration of K₂[CrF₅·H₂O] leads to anhydrous orthorhombic K₂CrF₅: a = 7.334(2) Å, b = 12.804(4) Å, c = 20.151(5) Å, Z = 16, space group Pbcn (n^o 60), isostructural with K₂FeF₅.     

A Novel Adipate Bridged Supramolecular Layer: Crystal Structure of the Cobalt(II) Complex [(μ‐C6H8O4)4/2Co(μ‐H2O)2Co(H2O)4] · 4 H2O

The pale‐rose compound [(μ‐C₆H₈O₄)_4/2Co(μ‐H₂O)₂Co(H₂O)₄] · 4 H₂O was prepared from adipic acid and CoCO₃ in aqueous solution. The crystal structure (monoclinic, P2₁/n (no. 14), a = 8.061(1), b = 15.160(2), c = 9.708(2) Å, β = 90.939(7)°, Z = 2, R = 0.0405, wR² = 0.0971) consists of adipate bridged supramolecular [(μ‐C₆H₈O₄)_4/2Co(μ‐H₂O)₂Co(H₂O)₄] layers and hydrogen bonded H₂O molecules. The cobalt atoms Co1 and Co2 are distorted octahedrally coordinated by the O atoms of two bridging trans‐H₂O molecules and four bidentate adipate anions (Co1) and by the O atoms of two bridging trans‐H₂O molecules and four monodentate H₂O molecules (Co2), respectively. Equatorial bonds: d(Co1–O) = 2.048 Å (2 × ), 2.060 Å (2 × ); d(Co2–O) = 2.057 Å (2 × ), 2.072 Å (2 × ). Axial bonds: d(Co1–O) = 2.235 Å (2 × ); d(Co2–O) = 2.156 Å (2 × ).     

Peroxofluorokomplexe der Übergangsmetalle. VIII. Kristallstruktur von K2Ti(O2)F4 · 1/2 H2O. Strukturchemischer Vergleich und spektroskopische Daten der Verbindungen K2Ti(O2)F4 · xH2O (mit x = 1, 1/2, 0)

Transition Metal Peroxofluoro Complexes. VIII. Crystal Structure of K₂Ti(O₂)F₄. · 1/2H₂O. Structural Comparison and Spectroscopic Data of the Compounds K₂Ti(O)₂F₄ · xH₂O (x = 1, 1/2, 0) The yellow hemihydrat K₂Ti(O₂)F₄ · 1/2 H₂O crystallizes monoclinic (space group C2/c, a = 1680.5(6), b = 653.2(1), c = 1224.3(4) pm, β = 115.8(1)°, Z = 8, Rw = 0.038 for 1113 independent reflections). It contains isolated, dinuclear, di(μ-fluoro)-bridged [Ti₂(O₂)₂F₈]^4? anions, as known by orange coloured K₂Ti(O₂)F₄ · H₂O [1]. They are arranged in layers which are parallel to the (100) plane, whereas they are linked by hydrogen bonds forming infinite chains in K₂Ti(O₂)F₄ · 1/2 H₂O. Anhydrous K₂Ti(O₂)F₄ - even yellow - crystallizes monoclinic with a = 828.9(2), b = 1107.6(2), c = 1303.9(3) pm, β = 92.29(2)°. I.r. and Raman spectra of all compounds are listed and interpreted. On the basis of the UV spectra the different colours of some titaniumperoxofluoro compounds are discussed in relation to the titanium-peroxid bonding.     

Synthesis and crystal structure of Na2CaP2O7

Na₂CaP₂O₇ has been prepared in single crystal form by fusion techniques. The single crystal structure: a = 5.361(3), b = 7.029(3), c = 8.743(4)Å, α = 69.40(2), β = 89.02(3), γ = 88.78(4) °, V = 308.5(3)ų, space group P1 bar, Z = 2, D_calc = 2.799 mg/m³, R/R_w = 0.0445/0.0554 for 1434 observed reflections (F>4.0σ(F), shows a solid state form similar to that of K₂SrP₂O₇, K₂MnP₂O₇ and KaCdP₂O₇.     

Two Novel CuII Phenanthroline Adipato Complexes with π‐π Stacking Interactions: [Cu(phen)2(C6H8O4)] · 4.5 H2O and [(Cu2(phen)2Cl2)(C6H8O4)] · 4 H2O

The blue copper complex compounds [Cu(phen)₂(C₆H₈O₄)] · 4.5 H₂O ( 1 ) and [(Cu₂(phen)₂Cl₂)(C₆H₈O₄)] · 4 H₂O ( 2 ) were synthesized from CuCl₂, 1,10‐phenanthroline (phen) and adipic acid in CH₃OH/H₂O solutions. [Cu(phen)₂‐ (C₆H₈O₄)] complexes and hydrogen bonded H₂O molecules form the crystal structure of ( 1 ) (P1 (no. 2), a = 10.086(2) Å, b = 11.470(2) Å, c = 16.523(3) Å, α = 99.80(1)°, β = 115.13(1)°, γ = 115.13(1)°, V = 1617.5(5) ų, Z = 2). The Cu atoms are square‐pyramidally coordinated by four N atoms of the phen ligands and one O atom of the adipate anion (d(Cu–O) = 1.989 Å, d(Cu–N) = 2.032–2.040 Å, axial d(Cu–N) = 2.235 Å). π‐π stacking interactions between phen ligands are responsible for the formation of supramolecular assemblies of [Cu(phen)₂(C₆H₈O₄)] complex molecules into 1 D chains along [111]. The crystal structure of ( 2 ) shows polymeric [(Cu₂(phen)₂Cl₂)(C₆H₈O₄)_2/2] chains (P1 (no. 2), a = 7.013(1) Å, b = 10.376(1) Å, c = 11.372(3) Å, α = 73.64(1)°, β = 78.15(2)°, γ = 81.44(1)°, V = 773.5(2) ų, Z = 1). The Cu atoms are fivefold coordinated by two Cl atoms, two N atoms of phen ligands and one O atom of the adipate anion, forming [CuCl₂N₂O] square pyramids with an axial Cl atom (d(Cu–O) = 1.958 Å, d(Cu–N) = 2.017–2.033 Å, d(Cu–Cl) = 2.281 Å; axial d(Cu–Cl) = 2.724 Å). Two square pyramids are condensed via the common Cl–Cl edge to centrosymmetric [Cu₂Cl₂N₄O₂] dimers, which are connected via the adipate anions to form the [(Cu₂(phen)₂Cl₂)(C₆H₈O₄)_2/2] chains. The supramolecular 3 D network results from π‐π stacking interactions between the chains. H₂O molecules are located in tunnels.     

Contribution to the crystal chemistry of tetrametaphosphates (I)

Crystal structures of K₄P₄O₁₂ · 2H₂O and of two polymorphs of Na₂K₂P₄O₁₂ · 2H₂O are reported. K₄P₄O₁₂ · 2H₂O is triclinic P1 with a = 8.153(4), b = 8.222(4), c = 11.154(8) Å, α = 97.33(5), β = 95.46(5), γ = 88.92(5)°, and Z = 2. R = 0.021 for 2898 reflections. Na₂K₂P₄O₁₂ · 2H₂O has two crystalline forms: a triclinic one ($\text{P}\text{1}$) with a = 11.366(8), b = 7.908(5), c = 7.929(5) Å, α = 90.07(5), β = 106.85(5), γ = 95.66(5)°, and Z = 2, and a tetragonal one (P4₁) with a = 7.928(5), c = 21.66(2), and Z = 4. The crystal structures of the first and second crystalline forms have been solved with final R values of 0.022 for 2505 reflections and 0.036 for 1347 reflections, respectively. Crystal data and chemical preparations are given for Na₂(NH₄)₂P₄O₁₂ · 2H₂O and Na₂Rb₂P₄O₁₂ · 2H₂O, both isotypic with the triclinic form of Na₂K₂P₄O₁₂ · 2H₂O. Unit-cell dimensions are, respectively, a = 11.547(8), b = 8.012(5), c = 8.044(5) Å, α = 89.76(5), β = 106.22(5), and γ = 94.78(5)°, for the ammonium salt, and a = 11.577(8), b = 8.006(5), c = 8.032(5) Å, α = 89.79(5), β = 106.58(5), and γ = 95.19(5)° for the rubidium salt. In addition the crystal structures of the two crystalline forms of Na₄P₄O₁₂ · 4H₂O were reexamined in order to localize the hydrogen atoms and refine their positions.     

Oxydationsprodukte intermetallischer Phasen. III. Tieftemperaturformen von K2Sn2O3 und Rb2Sn2O3 und eine Notiz über K2Ge2O3

Oxidation Products of Intermetallic Compounds. III. Low Temperature Forms of K₂Sn₂O₃ and Rb₂Sn₂O₃ and a Notice about K₂Ge₂O₃ By controlled oxidation of KSn (at 320°C) and RbSn (at 410°C) with O₂ the hitherto unknown low temperature forms of K₂Sn₂O₃ (a = 8.4100(8) Å) and Rb₂Sn₂O₃ (a = 8.6368(8) Å) are obtained, which are isotopic with cubic K₂Pb₂O₃. Oxidation at higher temperatures (at 510–5207°C) leads to the well-known HT-forms. The Madelung Part of Lattic Energie, MAPLE, is calculated for both compounds. K₂Pb₂O₃, Rb₂Pb₂O₃, Cs₂Pb₂O₃, and Cs₂Sn₂O₃ have been prepared too by oxidation of KPb, RbPb, CsPb, and CsSn. Oxidation of KGe (at 400°C) leads to the first oxogermanate(II), K₂Ge₂O₃ (cubic a = 8.339(1) Å, isotypic with K₂Pb₂O₃) together with K₆Ge₂O₇.     

Crystal Structures of [Mn2(H2O)4(bpy)2(C8H12O4)2] · 2 H2O and [Mn(H2O)2(bpy)(C8H12O4)2/2] · H2O with bpy = 2,2′‐bipyridine

Reaction of MnSO₄ · H₂O, 2,2′‐bipyridine (bpy), suberic acid and Na₂CO₃ in CH₃OH/H₂O yielded a mixture of [Mn₂(H₂O)₄(bpy)₂(C₈H₁₂O₄)₂] · 2 H₂O ( 1 ) and [Mn(H₂O)₂‐ (bpy)(C₈H₁₂O₄)_2/2] · H₂O ( 2 ). In both complexes, the Mn atoms are octahedrally coordinated by two N atoms of one bpy ligand and four O atoms of two trans positioned H₂O molecules and two suberato ligands (d(Mn–O) = 2.107–2.328 Å; d(Mn–N) = 2.250–2.330 Å). The bis‐monodentate suberato ligands bridge Mn atoms to form dinuclear [Mn₂(H₂O)₄(bpy)₂(C₈H₁₂O₄)₂] complex molecules in 1 and 1D [Mn(H₂O)₂(bpy)(C₈H₁₂O₄)_2/2] chains in 2 . Via the intermolecular hydrogen bondings and π‐π stacking interactions, the dinuclear molecules in 1 are assembled into 2D networks parallel to (100), between which the crystal H₂O molecules are sandwiched. The polymeric chains in 2 are linked together by interchain hydrogen bonding and π‐π stacking interactions into 3D networks with the crystal H₂O molecules located in tunnels along [010]. Crystal data for 1 : P2₁/c (no. 14), a = 10.092(1) Å, b = 11.916(2) Å, c = 17.296(2) Å, β = 93.41(1)° and Z = 2. Crystal data for 2 : P2₁/c (no. 14), a = 11.176(2) Å, b = 9.688(1) Å, c = 37.842(6) Å, β = 90.06(1)° and Z = 8.     

Zur Koordinationschemie von cis-Trioxowolfram(VI)-Komplexen. Die Kristallstrukturen von LWO3 · 3 H2O, [L′WO2(OH)]Br, [LWO2Br]Br, [L2W2O5](S2O6) · 4 H2O und [LWO2(μ-O)WO(O2)2(OH2)] (L = 1,4,7-Triazacyclononan; L′ = 1,4,7-Trimethyl-1,4,7-triazacyclononan)

Coordination-chemistry of cis-Trioxotungsten(VI) Complexes. Crystal Structures of LWO₃ · 3 H₂O, [L′WO₂(OH)]Br, [LWO₂Br]Br, [L₂W₂O₅](S₂O₆) · 4 H₂O and [LWO₂(μ-O)WO(O₂)₂(OH₂)] (L = 1,4,7-Triazacyclonane; L′ = 1,4,7-Trimethyl-1,4,7-triazacyclononane) The cyclic triamines 1,4,7-triazacyclononane (L; C₆H₁₅N₃) and 1,4,7-trimethyl-1,4,7-triazacyclononane (L′; C₉H₂₁N₃) react in aqueous solution with WO₃ affording LWO₃ · 3 H₂O, 1 , and L′WO₃ · 3 H₂O, respectively, which yield [L′WO₂(OH)]Br, 2 , and [LWO₂Br]Br, 3 , in concentrated HBr solutions. In aqueous CH₃SO₃H solution 1 dimerizes. The iodide and dithionate 4 salts of [L₂W₂O₅]²⁺ have been isolated. In 35% H₂O₂ complex 1 yields the neutral species [LWO₂(μ-O)WO(O₂)₂(H₂O)] 5 . The crystal structures of 1 – 5 have been determined by X-ray analysis. Crystal data: 1 : P2₁/c; a = 7.729(2), b = 14.887(3), c = 10.774(2) Å, β = 90.77(2)°, Z = 4; 2 : Cc; 8.910(3), b = 12.220(6), c = 13.279(6) Å, β = 101.31(3)°, Z = 4; 3 : Cmc2₁, a = 8.857(5), b = 12.062(7), c = 11.218(7) Å, Z = 4; 4 : Cc, a = 17.601(7), b = 12.906(7), c = 14.107(8) Å, β = 124.08(4)°, Z = 4; 5 : P2₁2₁2₁; a = 8.452(4), b = 11.301(6), c = 13.750(6) Å, Z = 4.