Ein- und zweikernige Fluorokomplexe des Titan(III), Chrom(III) und Eisen(III) Darstellung und Struktur von (NMe4)(Ti(H2O)4F2)TiF6 · H2O, (NMe4)3Cr2F9 und (NMe4)3Fe2F9

Mono- and Dinuclear Fluoro Complexes of Titanium (III), Chromium (III), and Iron(III). Syntheses and Structures of (NMe₄) (Ti(H₂O)₄F₂)TiF₆ · H₂O, (NMe₄)₃Cr₂F₉, and (NMe₄)₃Fe₂F₉ The title compounds have been prepared by reaction of MCl₃ (M = Ti, Cr, Fe) with NMe₄F in dimethylformamide. (NMe₄)₃Cr₂F₉ and (NMe₄)₃Fe₂F₉ contain the face-sharing biocathedral M₂F₉^3? unit. The M…M distances are 277.1(1) and 289.8(3) pm in (NMe₄)₃Cr₂F₉ and (NMe₄)Fe₂F₉, respectively. (NMe₄)(Ti(H₂O)₄F₂)TiF₆ · H₂O contains trans-Ti^III(H₂O)₄F₂⁺ cations and Ti^IVF₆^2? anions. Crystal data: (NMe₄)₃Cr₂F₉: hexagonal, space group P6₃/m, a = 804.1(3), c = 1857.5(4) pm, Z = 2, 529 reflections, R = 0.049; (NMe₄)₃Fe₂F₉: hexagonal, space group P6₃/m, a = 804.7(5), c = 1 861.6(5) pm, Z = 2, 635 reflections, R = 0,046; (NMe₄)(Ti(H₂O)₄F₂)TiF₆ · H₂O: orthorhombic, space group Pbca, a = 776.9(2), b = 1 616.3(3), c = 2 428.6(7) pm, Z = 8, 2 784 reflections, R = 0,056.     

N(B(NMe2)2)(Si(NMe2)3)(Ti(NMe2)3), [N(Si(NMe2)3)(Ti(NMe2)2)]2 und N(SiMe3)(Si(NMe2)3)(Ti(NMe2)3) — Synthese und Charakterisierung neuer molekularer Einkomponentenvorläufer für nitridische und carbonitridische Keramiken

N(B(NMe₂)₂)(Si(NMe₂)₃) (Ti(NMe₂)₃), [N(Si(NMe₂)₃)(Ti(NMe₂)₂)]₂ und N(SiMe₃)(Si(NMe₂)₃)(Ti(NMe₂)₃) — Synthesis and Characterization of New Molecular Single-source Precursors for Nitride and Carbonitride Ceramics Synthesis and spectroscopic data of the title compounds are reported. [N(Si(NMe₂)₃)(Ti(NMe₂)₂)]₂ crystallizes in the space group P1 , a = 8.406(7), b = 10.673(8), c = 10.872(6) Å, α = 68.45(4)°, β = 71.72(4)°, γ = 78.11(7)°, 2 877 diffractometer data (F_o ? 2σF_o), R = 0.051. The compound is characterized by a planar four-membered Ti₂N₂-ring with exocyclic tris(dimethylamino)silyl substituents attached to the nitrogen atoms of the ring.     

Zwei Galliumfluorid-Ammoniakate: Ga(NH3)F3 und Ga(NH3)2F3

Two Gallium Fluoride Ammine Complexes: Ga(NH₃)F₃ and Ga(NH₃)₂F₃ Two gallium trifluoride ammines, Ga(NH₃)F₃ and Ga(NH₃)₂F₃, are obtained as single crystals through oxidation of gallium metal with NH₄HF₂ (Ga : NH₄HF₂ = 1 : 1.5) and NH₄F (Ga : NH₄F = 1 : 3.5), respectively, at 450 °C and 400 °C. Ga(NH₃)F₃ crystallizes with the non-centrosymmetric space group Abm2 (a = b = 544.6(2) pm, c = 986.6(4) pm) forming two-dimensional layers of [Ga(NH₃)F₅] octahedra. The addition of another NH₃ molecule in Ga(NH₃)₂F₃ (orthorhombic, Immm, a = 700.0(3) pm, b = 724.7(2) pm, c = 393.1(1) pm) leads to one-dimensional rods of [Ga(NH₃)₂F₄] octahedra running parallel [001] which are stacked in the [010] direction. Infrared spectra suggest hydrogen bonding (N–H…F) in Ga(NH₃)F₃, for Ga(NH₃)₂F₃ an unequivocal statement is not possible.     

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.     

Dimers of Ag2+ Ions – Synthesis and Characterization of the Quaternary Silver Fluoride Ag2ZnZr2F14 with [Ag2F7]3– Units

Deep blue‐violet colored powder samples of Ag₂ZnZr₂F₁₄ were synthesized by heating Zn(NO₃)₂·4H₂O, Ag and ZrOCl₂·8H₂O at 300 °C under fluorine atmosphere. The crystal structure of Ag₂ZnZr₂F₁₄ was refined from X‐ray powder diffraction data using the Rietveld method (C2/m, a = 9.0206(1) Å, b = 6.6373(1) Å, c = 9.0563(1) Å, β = 90.44(1)°, Z = 2). The structure is derived from the isotypic Ag₃Zr₂F₁₄ by replacing only one of the two crystallographically different Ag²⁺ ions with Zn²⁺ ions, thus leading to discrete Ag₂F₇ dimers. These dimers are connected via nearly linear Ag–F···F–Ag bridges with short F···F distances of 2.33 Å to form two‐legged ladders. Magnetic susceptibility measurements and density functional calculations show that the two Ag²⁺ ions in each Ag₂F₇ dimer are strongly coupled antiferromagnetically.     

Das Monoammoniakat des Galliumamidfluorids: Ga(NH3)(NH2)F2

The Monoammoniate of Gallium Amide Fluoride, Ga(NH₃)(NH₂)F₂ The oxidation of gallium metal with NH₄F leads at 325 °C in the presence of indium to single crystals of Ga(NH₂)F₂ · NH₃ [monoclinic, C2/m (no. 12), a = 1053.1(1), b = 557.4(1), c = 484.2(3) pm, β = 90.04(4)]. The crystal structure is built up from layers of corner-bridged [Ga(NH₃)₂F₄] and [Ga(NH₂)₂F₄] octahedra, respectively. The infrared spectrum proves the existence of the amide group in Ga(NH₂)F₂ · NH₃.     

Primitive cubic packing of anions in Cs4[Re6Te8(CN)6]· 2H2O and Ba2[Re6Te8(CN)6] · 12H2O crystals

Crystal structures of Cs₄[Re₆Te₈(CN)₆]·2H₂O (1) and Ba₂[Re₆Te₈(CN)₆]· 12H₂O (2) are determined. Crystals 1 are orthorhombic, a = 14,282(1), b = 12.910(1), c = 18.040(1) Å, V_cell = 3326.3(8) ų, space group Pbcn, Z = 4, d_calc = 5.715 g/cm³, R(F) = 0.0482 for 3193 F_hkl > 4σ(F). Crystals 2 are triclinic, a = 9.671(3), b = 9.697(4), c = 11.039(4) Å, α = 89.86(3), β = 72.34(3), γ = 82.46(3)°, V_cell = 977.2(6) ų, space group P1, Z = 1, d^calc = 4.733 g/cm³, R(F) = 0.0490 for 3226 F_hkl > 4σ(F). In both structures, the [Re₆Te₈(CN)₆]^4? anions form a distorted primitive cubic packing with distances between the centers 9.02-9.63 Å in 1 and 9.70-11.04 Å in 2. The Cs⁺ cations in 1 lie near the face centers of the cubes formed by the onions. In 2, cation pairs (Ba²⁺)₂ bonded to two solvate water molecules are formed; the pairs lie at the centers of the anion cubes. In structures 1 and 2, there are shortened contacts between the tellurium atoms belonging to the neighboring anions (3.75-4.09 and 3.95-4.22 Å, respectively).     

Synthesis and Crystal Structures of the Novel Tetrameric Nitrido Complexes [{cyclo-ReN}4(S2CNEt2)6(MeOH)2(PPh3)2][BPh4]2 · CH2Cl2 · 2 H2O and [{cyclo-ReN}4(S2CNEt2)4Cl4(PMe2Ph)4] · 2 acetone

Novel tetrameric rhenium(V) complexes have been prepared from [ReNCl₂(PPh₃)₂] and [ReN(PMe₂Ph)(S₂CNEt)₂], respectively. [ReNCl₂(PPh₃)₂] reacts with 1.5 equivalents of KS₂CNEt₂ in methanol to yield the unusual dark red species [{cyclo-ReN}₄(S₂CNEt₂)₆(MeOH)₂(PPh₃)₂][BPh₄]₂ · CH₂Cl₂ · 2 H₂O ( 1 ). The crystal structure of the tetramer (triclinic, space group P1, a = 13.842(2), b = 15.213(2), c = 16.796(3) Å, α = 67.88(1), β = 70.90(1), γ = 88.05(1)°, U = 3080.2(8) ų, Z = 1) shows four rhenium atoms in a square configuration which are bridged via linear asymmetric Re≡N–Re groups with bond lengths of about 169 and 203 pm. The molecule contains a centre of symmetry with two distinct octahedral rhenium environments. The first rhenium environment contains two bidentate dithiocarbamate ligands which complete the octahedral geometry and the second contains a bidentate dithiocarbamate ligand, coordinated methanol and has retained a single phosphine coligand. A symmetric compound containing the {cyclo-ReN}₄ core is obtained from the reaction of [ReN(PMe₂Ph)(S₂CNEt₂)₂] with Al₂Cl₆ in acetone. [{cyclo-ReN}₄(S₂CNEt₂)₄Cl₄(PMe₂Ph)₄] · 2 acetone ( 2 ) forms red crystals (monoclinic, space group C2/c, a = 21.432(6), b = 13.700(3), c = 28.060(9) Å, β = 102.37(1)°, U = 8048(4) Å3, Z = 4) with each rhenium atom coordinated by a bidentate dithiocarbamato, a phosphine and a chloro ligand. The non-planar 8-membered {ReN}₄ ring contains asymmetric Re≡N–Re bridges (mean values: 1.69 Å and 2.029 Å, respectively). In contrast, reaction of [ReNCl(S₂CNEt₂)(PMe₂Ph)₂] with one equivalent of K[S₂CN(Me)CH₂CH₂NMe₃]I gave the mixed dithiocarbamato-cation [ReN(S₂CNEt₂)(S₂CN(Me)CH₂CH₂NMe₃)(PMe₂Ph)]⁺ ( 3 ) which was isolated as a tetraphenylborate salt.     

Synthese,Charakterisierung und Struktur von Mn3SiO4F2

Synthesis, Characterization, and Structure of Mn₃SiO₄F₂ Mn₃SiO₄F₂ was synthesized by chemical vapour transport in a temperature gradient (800 → 700 °C) using MnF₂ as precursor and iodine as transport agent. SiO₂ was provided from the wall of the used silica tubes. The chemical composition of the crystals was determined by EELS and EDX analysis. The structure of Mn₃SiO₄F₂ was determined and refined to R(|F|) = 0.039, wR(F²) = 0.087, respectively. The orthorhombic phase crystallizes in the space group Pnma (No. 62) with a = 10.758(2) Å, b = 9.145(1) Å, c = 4.850(1) Å and Z = 4. Two crystallographically different Mn‐atoms are surrounded by oxygene and fluorine octahedrally. Si is tetrahedrally surrounded only by oxygen. IR‐measurements proved that in Mn₃SiO₄F₂ no substitution of F^– by OH^– takes place as in the mineral norbergite (Mg₃SiO₄(OH,F)₂).     

Preparation and Crystal Structure of the Strontium Aluminium Fluoride Sr5Al2F16

Single crystals of Sr₅Al₂F₁₆ crystallize in colourless translucent plates and have been prepared by solid state synthesis, starting from stoichiometric mixtures of the binary fluorides. The crystal structure has been determined and refined from single crystal diffractometer data (orthorhombic, space group Ccca (no. 68), a = 7.4488(4) Å, b = 12.4714(7) Å, c = 14.1411(8) Å, V = 1313.67(13) ų, Z = 4, R[F ² > 2σ(F ²)] = 0.025; wR2(F ² all) = 0.056, 971 structure factors, 56 parameters) and can be derived from a slightly distorted c.c.p. arrangement where 7/8 of the c.c.p. positions are occupied by the metal atoms. The main features of the structure are AlF₆ octahedra and SrF₈ polyhedra with mean distances d(Al–F) = 1.791 Å and d(Sr–F) = 2.531 Å, respectively.     

Darstellung,Struktur und Schwingungsspektren der Oxofluorowolframate(VI) Cs2[WO3F2] und Cs3[W2O4F7]

Synthesis, Structure, and Vibrational Spectra of the Oxofluorotungstates(VI) Cs₂[WO₃F₂] and Cs₃[W₂O₄F₇] Cs₂[WO₃F₂] crystallizes from a melt with the same composition. The orthorhombic unit cell with a = 6.779(2), b = 7.668(1) and c = 11.626(3) Å, space group Pn2₁a, contains 4 formula units. The WO₃F₂^2? anion is polymer, W octahedrally coordinated according to the results of the X-ray crystal structure determination. Planar dioxodifluoro groups are linked into chains by oxygen atoms. The lengths of the W? O bonds are alternating. Cs₃[W₂O₄F₇] crystallizes trigonal, space group P3 m1, with a = 21.118(4) and c = 8.434(2) Å, Z = 9. The structure consists of two sets of crystallographically non equivalent dimeric anions with the formula [O₂F₃W? F? WO₂F₃]^3?. Part of the ligand atoms are disordered. The vibrational spectra of both compounds show the presence of cis-dioxo groups of the terminal ligands.     

Phosphaniminato‐ und Phosphanimin‐Komplexe von Nickel(II). Die Kristallstrukturen von [Ni(O3SCF3)(NPMe3)]4, [Ni4Br5{NP(NMe2)3}3], [NiBr2{HNP(NMe2)3}2] und [Ni(PMePh2)4]

Phosphoraneiminato‐ and Phosphaneimine Complexes of Nickel(II). Crystal Structures of [Ni(O₃SCF₃)(NPMe₃)]₄, [Ni₄Br₅{NP(NMe₂)₃}₃], [NiBr₂{HNP(NMe₂)₃}₂], and [Ni(PMePh₂)₄] Black‐violet single crystals of [Ni(O₃SCF₃)(NPMe₃)]₄ ( 1 ) have been prepared from [NiBr(NPMe₃)]₄ and copper(I)triflate by metathesis reaction. The nickel atoms are associated via μ₃‐N bridges of the (NPMe₃^–) groups to form a heterocubane. The triflate ions are bonded to the Ni atoms in a chelate fashion. Blue single crystals of [Ni₄Br₅{NP(NMe₂)₃}₃] ( 2 ) are obtained by the reaction of NiBr₂ with Me₃SiNP(NMe₂)₃ in boiling toluene in the presence of sodium fluoride. The Ni atoms in 2 are associated with three μ₃‐bridged nitrogen atoms of the (NP(NMe₂)₃^–) groups as well as by a μ₃‐Br atom to give a distorted heterocubane. Deep blue single crystals of the phosphaneimine complex [NiBr₂{HNP(NMe₂)₃}₂] ( 3 ) are formed from Me₃SiNP(NMe₂)₃ and NiBr₂ in boiling dichloromethane. In 3 the Ni atom is tetrahedrally coordinated by the bromine atoms and by the nitrogen atoms of the phosphane imine molecules. Pale red crystals of [Ni(PMePh₂)₄] ( 4 ) have been obtained by the reaction of [NiBr(NPMe₃)]₄ with lithium phenylacetilyde in the presence of PMePh₂. In 4 the Ni atom is distorted tetrahedrally coordinated by the phosphorus atoms of the phosphane molecules with Ni–P distances of 219.9 pm in average. 1 – 4 have been characterized by crystallographic X‐ray analyses. 1 : Space group P2₁/n, Z = 4, lattice dimensions at 193 K: a = 1566.7(2); b = 1479.9(1); c = 1960.6(2) pm; β = 105.908(9)°; R = 0.0443. 2 · 3 CH₂Cl₂: Space group P2₁/c, Z = 4, lattice dimensions at 293 K: a = 1226.0(3); b = 1614.0(3); c = 2406.0(5) pm; β = 92.34(3)°; R = 0.0703. 3 : Space group C2/c, Z = 4, latttice dimensions at 203 K: a = 1840.7(1); b = 810.1(1); c = 1607.2(2) pm; β = 94.74(1)°, R = 0.0340. 4 : Space group P1, Z = 2, lattice dimensions at 223 K: a = 1053.1(2); b = 1315.0(3); c = 1674.5(3) pm; α = 81.55(1)°; β = 79.15(2)°; γ = 84.91(2)°; R = 0.0497.     

The Oxidation of Heterogeneous Tl/Ni/P‐Alloys — Preparation and Crystal Structures of the Thallium Nickel Phosphates TlNi4(PO4)3, Tl4Ni7(PO4)6, and Tl2Ni4(P2O7)(PO4)2

Single crystals of the first anhydrous thallium nickel phosphates were prepared by reaction of heterogeneous Tl/Ni/P alloys with oxygen. TlNi₄(PO₄)₃ (pale‐yellow, orthorhombic, space group Cmc2₁, a = 6.441(2)Å, b = 16.410(4)Å, c = 9.624(2)Å, Z = 4) crystallizes with a structure closely related to that of NaNi₄(PO₄)₃. Tl₄Ni₇(PO₄)₆ (yellow‐brown, monoclinic, space group Cm, a = 10.711(1)Å, b = 14.275(2)Å, c = 6.688(2)Å, β = 103.50(2)°, Z = 8) is isotypic with Na₄Ni₇(PO₄)₆, and Tl₂Ni₄(P₂O₇)(PO₄)₂ (brown, monoclinic, space group C2/c, a = 10.389(2)Å, b = 13.888(16)Å, c = 18.198(3)Å, β = 103.1(2)°, Z = 8) adopts the K₂Ni₄(P₂O₇)(PO₄)₂ structure. Tl₂Ni₄(P₂O₇)(PO₄)₂ could also be prepared in nearly single phase form by reaction of Tl₂CO₃, NiO, and (NH₄)₂HPO₄.     

The Reduction of AuF3 in Super Acidic Solution

AuF₃ is reduced in superacidic HF/SbF₅ solutions giving three products. 1. Orange [Au₃F₈·2SbF₅]. It has a layered structure built up by square planar Au^IIF₄ and Au^IIIF₄ units: Crystal structure: space group P2₁/c, a = 9.049(2), b = 8.424(1), c = 9.645(1)Å, β = 115.08(1)°. 2. Black [Au₃F₇·3SbF₅] has a ribbon structure, similarly built up by square planar Au^IIF₄ and Au^IIIF₄ units: Crystal structure: space group Pc, a = 9.991(1), b = 10.728(1), c = 15.222(1)Å, β = 95.304(2)°. 3. Yellow green [(Au(HF)₂] (SbF₆)₂·2HF with square planar Au^IIF₄ units that are formed by two fluorine atoms of the anions and two HF molecules as complex ligands. Crystal structure: Space group P¯, a = 5.482(1), b = 5.848(1), c = 9.309(2)Å, α = 89.522(4), β = 85.635(4), γ = 87.509(4)°.     

Synthese und Kristallstrukturen von NH4[Si(NH3)F5] und [Si(NH3)2F4]

Synthesis and Crystal Structures of NH₄[Si(NH₃)F₅] and [Si(NH₃)₂F₄] Single crystals of NH₄[Si(NH₃)F₅] and [Si(NH₃)₂F₄] are obtained by reaction of silicon powder with NH₄HF₂ in sealed Monel ampoules at 400°C. NH₄[Si(NH₃)F₅] crystallizes with the tetragonal space group P4/n (no. 85) with a = 614.91(7) pm, c = 721.01(8) pm, Z = 2. Characteristic for the structure is the anionic octahedron [Si(NH₃)F₅]^?. Si(NH₃)₂F₄ crystallizes with the monoclinic space group P2₁/c (no. 14) with a = 506.9(1) pm, b = 728.0(1) pm, c = 675.9(1), β = 93,21(2)°, Z = 2. Trans-[Si(NH₃)₂F₄] molecules are characteristic for this structure.     

The Single Crystal Structures of the Copper Usovites Ba2CaCuV2F14 and Ba2CaCuCr2F14

The results of single crystal X‐ray structure determinations are reported for Ba₂CaCuV₂F₁₄ (a = 1383.6(3), b = 540.89(8), c = 1493.1(3) pm, β = 91.65(3)°) and Ba₂CaCuCr₂F₁₄ (a = 1381.1(5), b = 535.5(1), c = 1481.4(6) pm, β = 91,50(4)°), both isotypic with usovite (space group C2/c, Z = 4). The resulting average distances are V‐F: 193.8 pm, Cr‐F: 190.7 pm, and Cu‐F: 209.2 resp. 207.1 pm for the Jahn‐Teller elongated [CuF₆] octahedra. Within the cross‐linked double chains of octahedra F‐bridged trimers M‐Cu‐M, magnetically studied earlier, are confirmed and discussed.     

Two Modifications of NH4HPO3F: Synthesis and Crystal Structure

The α and β modifications of NH₄HPO₃F were synthesized and characterized with single crystal X‐ray diffraction. The crystal structure of α‐NH₄HPO₃F determined at 180 K is monoclinic, space group P2₁/n, with a = 7.4650(1), b = 15.586(2), c = 7.5785(9) Å, β = 108.769(9)°, V = 834.9(2) ų, Z = 8, and R₁ = 0.0376 and wR₂ = 0.0818. β‐NH₄HPO₃F measured at 310 K crystallizes in the triclinic space group, P 1, with a = 7.481(1), b = 7.511(1), c = 7.782(1) Å, α = 84.31(1), β = 84.20(1), γ = 68.67(2)°, V = 404.31(9) ų, Z = 4, and R₁ = 0.0254 and wR₂ = 0.0735. A phase transition was not observed between 180 and 310 K for β‐NH₄HPO₃F. Both modifications of NH₄HPO₄F consist of HPO₃F^– and NH₄⁺ units. Two pairs of two unique anions are linked to each other by O–H…O hydrogen bonds to form cyclic tetramers held together by N–H…O bonds. No O–H…F or N–H…F bonds were observed.     

Kristallstrukturen und thermisches Verhalten von Metalldihydrogenphosphat‐HF‐Addukten MH2PO4 · HF (M = K,Rb, Cs) mit Wasserstoffbrückenbindungen vom Typ F–H…O

Structures and Thermal Behaviour of Alkali Metal Dihydrogen Phosphate HF Adducts, MH₂PO₄ · HF (M = K, Rb, Cs), with Hydrogen Bonds of the F–H…O Type Three HF adducts of alkali metal dihydrogen phosphates, MH₂PO₄ · HF (M = K, Rb, Cs), have been isolated from fluoroacidic solutions of MH₂PO₄. KH₂PO₄ · HF crystallizes monoclinic: P2₁/c, a = 6,459(2), b = 7,572(2), c = 9,457(3) Å, β = 101,35(3)°, V = 453,5(3) ų, Z = 4. RbH₂PO₄ · HF and CsH₂PO₄ · HF are orthorhombic: Pna2₁, a = 9,055(3), b = 4,635(2), c = 11,908(4) Å, V = 499,8(3) ų, Z = 4, and Pbca, a = 7,859(3), b = 9,519(4), c = 14,744(5) Å, V = 1102,5(7) ų, Z = 8, respectively. The crystal structures of MH₂PO₄ · HF contain M⁺ cations, H₂PO₄^– anions and neutral HF molecules. The H₂PO₄^– anions are connected to layers by O–H…O hydrogen bonds (2,53–2,63 Å), whereas the HF molecules are attached to the layers via very short hydrogen bonds of the F‐H…O type (2,36–2,38 Å). The thermal decomposition of the adducts proceeds in three steps. The first step corresponds to the release of mainly HF and a smaller quantity of water. In the second and third steps, water evolution caused by condensation of dihydrogen phosphate is the dominating process whereas smaller amounts of HF are also released.     

Crystal Structure of the Mixed‐Valent Basic Mercury Nitrate HgI2(NO3)2·HgII(OH)(NO3)·HgII(NO3)2·4HgIIO [= Hg8O4(OH)(NO3)5]

Light‐yellow single crystals of the mixed‐valent mercury‐rich basic nitrate Hg₈O₄(OH)(NO₃)₅ were obtained as a by‐product at 85 °C from a melt consisting of stoichiometric amounts of (Hg^I₂)(NO₃)₂·2H₂O and Hg^II(OH)(NO₃). The title compound, represented by the more detailed formula Hg^I₂(NO₃)₂·Hg^II(OH)(NO₃)·Hg^II(NO₃)₂·4Hg^IIO, exhibits a new structure type (monoclinic, C2/c, Z = 4, a = 6.7708(7), b = 11.6692(11), c = 24.492(2) Å, β = 96.851(2)°, 2920 structure factors, 178 parameters, R1[F² > 2σ(F²)] = 0.0316) and is made up of almost linear [O‐Hg^II‐O] and [O‐Hg^I‐Hg^I‐O] building blocks with typical Hg^II‐O distances around 2.06Å and a Hg^I‐O distance of 2.13Å. The Hg₂²⁺ dumbbell exhibits a characteristic Hg‐Hg distance of 2.5079(7) Å. The different types of mercury‐oxygen units form a complex three‐dimensional network exhibiting large cavities which are occupied by the nitrate groups. The NO₃^? anions show only weak interactions between the nitrate oxygen atoms and the mercury atoms which are at distances > 2.6Å from one another. One of the three crystallographically independent nitrate groups is disordered.     

Synthese und Struktur neuer Natriumhydrogensulfate Na(H3O)(HSO4)2; Na2(HSO4)2(H2SO4) und Na(HSO4)(H2SO4)2

Synthesis and Structure of New Sodium Hydrogen Sulfates Na(H₃O)(HSO₄)₂, Na₂(HSO₄)₂(H₂SO₄), and Na(HSO₄)(H₂SO₄)₂ Three acidic sodium sulfates have been synthesized from the system sodium sulfate/sulfuric acid and have been crystallographically characterized. Na(H₃O)(HSO₄)₂ ( A ) crystallizes in the space group P2₁/c with the unit cell parameters a = 6.974(2), b = 13.086(2), c = 8.080(3) Å, α = 105.90(4)°, V = 709.1 Å3, Z = 4. Na₂(HSO₄)₂(H₂SO₄) ( B ) is orthorhombic (space group Pna2₁) with the unit cell parameters a = 9.970(2), b = 6.951(1), c = 13.949(3) Å, V = 966.7 ų and Z = 4. Na(HSO₄)(H₂SO₄)₂ ( C ) crystallizes in the triclinic space group P1 with the unit cell parameters a = 5.084(1), b = 8.746(1), c = 11.765(3) Å, α = 68.86(2)°, β = 88.44(2)°, γ = 88.97(2)°, V = 487.8 Å3 and Z = 2. All three compounds contain SO₄ tetrahedra as HSO₄^? anions and additionally in B and C in form of H₂SO₄ molecules. The ratio H:SO₄ determines the connectivity degree in the hydrogen bond system. In A , there are zigzag chains and dimers additionally connected via oxonium ions. Complex chains consisting of cyclic trimers (two HSO₄^? and one H₂SO₄) are present in B . In structure C , several parallel chains are connected to columns due to the greater content of H₂SO₄. Sodium cations show a distorted octahedral coordination by oxygen in all three structures, the NaO₆ octahedra being “isolated” (connected via SO₄ tetrahedra only) in A . Pairs of octahedra with common edge form Na₂O₁₀ dimeric units in C . Such double octahedra are connected via common corners forming zigzag chains in B .