Die Kristallstrukturen von (DDI)2[Sb2F6O] und (DDI)2[Sb3F7O2] (DDI = 1, 3‐Diisopropyl‐4, 5‐dimethylimidazolium) — Ein Beitrag zur Hydrolyse von SbF3 [1]

The Crystal Structures of (DDI)₂[Sb₂F₆O] and (DDI)₂[Sb₃F₇O₂] (DDI = 1,3‐Diisopropyl‐4,5‐dimethylimidazolium) — a Contribution to the Hydrolysis of SbF₃ [1] The salts (DDI)₂[Sb₂F₆O] ( 2 ) and (DDI)₂[Sb₃F₇O₂] ( 3 ), (DDI = 1,3‐diisopropyl‐4,5‐dimethylimidazolium) are obtained by hydrolysis of C₁₁H₂₀N₂SbF₃ ( 1 ). The anion [Sb₂F₆O]^2? consists of two SbF₂ fragments linked by a symmetrical oxygen bridge and two unsymmetrical fluorine bridges to form a distored ψ‐octahedral coordination sphere at the antimony atoms. In [Sb₃F₇O₂]^2?, two SbF₂ units are linked by a symmetrical fluorine bridge, while the third antimony atom is connected with each SbF₂ fragment by a symmetrical oxygen and an unsymmetrical fluorine bridge. The antimony atoms adopt the centres of strongly distored ψ‐polyhedra.     

Anionische Antimon(III)-Fluorokomplexe mit protonierten Azakronenethern als Gegenionen. Strukturen und Mößbauerspektren von [H2cyclam]2[Sb4F16] · 2 H2O, [H4cyclam][Sb2F10] · 2 HF und [H4(tetramethyl)cyclam]2[Sb4F15][HF2][F]4 (cyclam = 1,4,7,11-Tetraazacyclotetradecan)

Anionic Antimony(III) Fluoro Complexes with protonated Azacrownethers as Counterions. Crystal Structures and Mößbauer Spectra of [H₂cyclam]₂[Sb₄F₁₆] · 2H₂O, [H₄cyclam][Sb₂F₁₀] · 2 HF, and [H₄(tetramethyl)cyclam]₂[Sb₄F₁₅][HF₂][F]₄ (cyclam = 1,4,7,11-Tetraazacyclotetradecane) The title compounds are formed by reaction of SbF₃ with the respective azacrownether. [H₂cyclam]₂[Sb₄F₁₆] · 2 H₂O contains tetrameric anions which weakly associate to chains. The [H₂cyclam]²⁺ ions possess an unusual conformation due to intramolecular hydrogen bonds. [H₄cyclam][Sb₂F₁₀] · 2HF contains the dimeric hitherto unknown [Sb₂F₁₀]^4? ion; two HF molecules are attached to it by hydrogen bonds. The structure of [H₄(tetramethyl)cyclam]₂[Sb₄F₁₅][HF₂][F]₄ is made up of the two dimensional polymeric [HSb₄F₁₇]^4? anion. The tetra-protonated tetramethylcyclam ions form host-guest complexes with fluoride ions.     

Synthesen und Schwingungsspektren der homoleptischen Acetonitrilkomplex-Kationen [Au(NCCH3)2]+, [Pd(NCCH3)4]2+, [Pt(NCCH3)4]2+ und des Adduktes CH3CN · SbF5. Kristallstrukturen der Salze [M(NCCH3)4][SbF6]2 · CH3CN,M = Pd,Pt

The Syntheses and Vibrational Spectra of the Homoleptic Metal Acetonitrile Cations [Au(NCCH₃)₂]⁺, [Pd(NCCH₃)₄]²⁺, [Pt(NCCH₃)₄]²⁺, and the Adduct CH₃CN · SbF₅. The Crystal and Molecular Structures of [M(NCCH₃)₄][SbF₆]₂ · CH₃CN, M = Pd or Pt Solvolyses of the homoleptic metal carbonyl salts [M(CO)₄][Sb₂F₁₁]₂, M = Pd or Pt, in acetonitrile leads at 50 °C both to complete ligand exchange for the cations as well as to a conversion of the di-octahedral anion [Sb₂F₁₁]^– into [SbF₆]^– and the molecular adduct CH₃CN · SbF₅ according to: [M(CO)₄][Sb₂F₁₁]₂ + 7 CH₃CN → [M(NCCH₃)₄][SbF₆]₂ · CH₃CN + 2 CH₃CN · SbF₅ + 4 CO M = Pd, Pt The monosolvated [M(NCCH₃)₄][SbF₆]₂ · CH₃CN are obtained as single crystals from solution and are structurally characterized by single crystal x-ray diffraction. Both salts are isostructural. The cations are square planar but the N–C–C-sceletial groups of the ligands depart slightly from linearity. The new acetonitrile complexes as well as [Au(NCCH₃)₂][SbF₆] and the adduct CH₃CN · SbF₅ are completely characterized by vibrational spectroscopy.     

Group 6 Oxyfluoro-Anion Salts of [XeF5]+ and [Xe2F11]+: Syntheses and Structures of [XeF5][M2O2F9] (M=Mo,W), [Xe2F11][M′OF5] (M′=Cr,Mo, W), [XeF5][HF2]⋅CrOF4, and [XeF5][WOF5]⋅XeOF4

The reactions of the fluoride-ion donor, XeF₆, with the fluoride-ion acceptors, M′OF₄ (M′=Cr, Mo, W), yield [XeF₅]⁺ and [Xe₂F₁₁]⁺ salts of [M′OF₅]⁻ and [M₂O₂F₉]⁻ (M=Mo, W). Xenon hexafluoride and MOF₄ react in anhydrous hydrogen fluoride (aHF) to give equilibrium mixtures of [Xe₂F₁₁]⁺, [XeF₅]⁺, [(HF)_nF]⁻, [MOF₅]⁻, and [M₂O₂F₉]⁻ from which the title salts were crystallized. The [XeF₅][CrOF₅] and [Xe₂F₁₁][CrOF₅] salts could not be formed from mixtures of CrOF₄ and XeF₆ in aHF at low temperature (LT) owing to the low fluoride-ion affinity of CrOF₄, but yielded [XeF₅][HF₂]⋅CrOF₄ instead. In contrast, MoOF₄ and WOF₄ are sufficiently Lewis acidic to abstract F⁻ ion from [(HF)_nF]⁻ in aHF to give the [MOF₅]⁻ and [M₂O₂F₉]⁻ salts of [XeF₅]⁺ and [Xe₂F₁₁]⁺. To circumvent [(HF)_nF]⁻ formation, [Xe₂F₁₁][CrOF₅] was synthesized at LT in CF₂ClCF₂Cl solvent. The salts were characterized by LT Raman spectroscopy and LT single-crystal X-ray diffraction, which provided the first X-ray crystal structure of the [CrOF₅]⁻ anion and high-precision geometric parameters for [MOF₅]⁻ and [M₂O₂F₉]⁻. Hydrolysis of [Xe₂F₁₁][WOF₅] by water contaminant in HF solvent yielded [XeF₅][WOF₅]⋅XeOF₄. Quantum-chemical calculations were carried out for M′OF₄, [M′OF₅]⁻, [M′₂O₂F₉]⁻, {[Xe₂F₁₁][CrOF₅]}₂, [Xe₂F₁₁][MOF₅], and {[XeF₅][M₂O₂F₉]}₂ to obtain their gas-phase geometries and vibrational frequencies to aid in their vibrational mode assignments and to assess chemical bonding.     

Chromium Oxide Tetrafluoride and Its Reactions with Xenon Hexafluoride; the [XeF5]+ and [Xe2F11]+ Salts of the [CrVIOF5]−, [CrVOF5]2−, [CrV2O2F8]2−, and [CrIVF6]2− Anions

Molten mixtures of XeF₆ and Cr^VIOF₄ react by means of F₂ elimination to form [XeF₅][Xe₂F₁₁][Cr^VOF₅] ⋅ 2 Cr^VIOF₄, [XeF₅]₂[Cr^IVF₆] ⋅ 2 Cr^VIOF₄, [Xe₂F₁₁]₂[Cr^IVF₆], and [XeF₅]₂[Cr^V₂O₂F₈], whereas their reactions in anhydrous hydrogen fluoride (aHF) and CFCl₃/aHF yield [XeF₅]₂[Cr^V₂O₂F₈] ⋅ 2 HF and [XeF₅]₂[Cr^V₂O₂F₈] ⋅ 2 XeOF₄. Other than [Xe₂F₁₁][M^VIOF₅] and [XeF₅][M^VI₂O₂F₉] (M=Mo or W), these salts are the only Group 6 oxyfluoro-anions known to stabilize noble-gas cations. Their reaction pathways involve redox transformations that give [XeF₅]⁺ and/or [Xe₂F₁₁]⁺ salts of the known [Cr^VOF₅]²⁻ and [Cr^IVF₆]²⁻ anions, and the novel [Cr^V₂O₂F₈]²⁻ anion. A low-temperature Raman spectroscopic study of an equimolar mixture of solid XeF₆ and CrOF₄ revealed that [Xe₂F₁₁][Cr^VIOF₅] is formed as a reaction intermediate. The salts were structurally characterized by LT single-crystal X-ray diffraction and LT Raman spectroscopy, and provide the first structural characterizations of the [Cr^VOF₅]²⁻ and [Cr^V₂O₂F₈]²⁻ anions, where [Cr^V₂O₂F₈]²⁻ represents a new structural motif among the known oxyfluoro-anions of Group 6. The X-ray structures show that [XeF₅]⁺ and [Xe₂F₁₁]⁺ form ion pairs with their respective anions by means of Xe- - -F–Cr bridges. Quantum-chemical calculations were carried out to obtain the energy-minimized, gas-phase geometries and the vibrational frequencies of the anions and their ion pairs and to aid in the assignments of their Raman spectra.     

Donor-Stabilised [SbF4]+: SbF5 as a Fluoride-Ion Donor

Antimony pentafluoride is a strong Lewis acid and fluoride-ion acceptor that has not previously demonstrated any discreet fluoride-ion donor properties. The first donor-stabilised [SbF₄]⁺ cations were prepared from the autoionisation of SbF₅ in the presence of bidentate N-donor ligands 2,2’-bipyridine (bipy) and 1,10-phenanthroline (phen) as their [SbF₆]⁻ salts. The [SbF₄(N−N)][Sb₂F₁₁] (N−N=bipy, phen) salts were synthesised by the addition of one equivalent of SbF₅⋅SO₂ to [SbF₄(N−N)][SbF₆] in liquid SO_2. The salts show remarkable stability and were characterised by Raman spectroscopy and multinuclear NMR spectroscopy. The crystal structures of [SbF₄(phen)][SbF₆] ⋅ 3CH₃CN and [SbF₄(phen)][SbF₆] ⋅ 2SO₂ were determined, showing distorted octahedral cations. DFT calculations and NBO analyses reveal that significant degree of electron-pair donation from N to Sb stabilizes [SbF₄]⁺ with the Sb−N bond strength being approximately two thirds of that of the Sb−F bonds in these cations and the cationic charge being primarily ligand-centred.     

Hydrolysis of antimony(III) fluoride complexes

Vibrational and ¹⁷O NMR spectroscopy in combination with quantum chemical calculations are used to investigate the hydrolysis of antimony(III) fluoride complexes. A hydrolytic decomposition of SbF₃ and [SbF₄]^? is accompanied by oligomerization with the formation of edge-and corner-connected dimers ([Sb₂O₂F₄]^2?, [Sb₂OF₈]^4?) and trimers ([Sb₃O₃F₆]^3?, [Sb₃OF₉]^2?) with bridging oxygen atoms. The hydrolysis of [SbF₄]^? is also characterized by the presence in the solution of a discrete cation of [SbF₅]^2? which is least hydrolized. Only a partial isomorphic substitution of fluoride ion by hydroxide one is possible, which is reflected in the composition of K₂Sb(OH)_xF_5?x (x = 0.3) crystals isolated from the fluoride aqueous solution.     

THE METASTABLE PARTIALLY POSITIVELY CHARGED Se6 MOLECULE: PREPARATION,CHARACTERISATION AND X-RAY CRYSTAL STRUCTURE OF [Ag2(Se6)(SO2)2][Sb(OTeF5)6]2, [Ag2Se6][AsF6]2 AND [AgSe6][Ag2(SbF6)3]

Reactions designed to give Se₆[Sb(OTeF₅)₆]₂ by the reaction of Se₂Br₂, 4Se, and 2Ag[Sb(OTeF₅)₆] lead to products that include [Ag₂(Se₆)(SO₂)₂][Sb(OTeF₅)₆]₂(1). The distorted cubic (Ag₂Se₆ ²⁺) _n consists of a Se₆ molecule bicapped by two silver cations (local D_3d sym.). Reactions of AgMX₆ (M = As, Sb) with selenium in liquid SO₂ yielded crystals of [Ag₂Se₆][AsF₆]₂ (2) and [AgSe₆][Ag₂(SbF₆)₃] (3). Both salts contain stacked arrays of [AgSe₆]⁺ half-sandwich cationic units. [Ag₂Se₆][AsF₆]₂ in addition contains stronger, linear Se─Ag─Se horizontal linkages between the vertically stacked cationic columns. [AgSe₆][Ag₂(SbF₆)₃] features a remarkable three-dimensional [Ag₂(SbF₆)₃]^? anion held together by strong Sb─F···Ag contacts between component Ag⁺ and SbF₆ ^? ions. Hexagonal channels through this honeycomb-like anion are filled by the stacked [AgSe₆ ⁺]_x.     

Convenient Access to α‐Fluorinated Alkylammonium Salts

A series of novel α‐fluoroalkyl ammonium salts was obtained from the corresponding cyano compounds or nitriles by reaction with anhydrous HF. Room‐temperature stable trifluoromethyl ammonium salts were obtained in quantitative yield in a one‐step reaction at ambient temperature from the commercially available starting materials BrCN or ClCN. The novel cations [CF₃CF₂NH₃]⁺, [HCF₂CF₂NH₃]⁺, and [(NH₃CF₂)₂]²⁺ were obtained from CF₃CN, HCF₂CN, and (CN)₂, respectively, and anhydrous HF. The aforementioned fluorinated ammonium cations were isolated as room temperature stable [AsF₆]^? and/or [SbF₆]^? salts, and characterized by multi‐nuclear NMR and vibrational spectroscopy. The salts [HCF₂NH₃][AsF₆] and [CF₃NH₃][Sb₂F₁₁] were characterized by their X‐ray crystal structure.     

Predominantly sigma-bonded metal carbonyl cations (sigma-carbonyls): new synthetic,structural, and bonding concepts in metal carbonyl chemistry

Predominantly σ‐bonded metal carbonyl cations (σ‐carbonyls) are conveniently generated in the Lewis superacid SbF₅ or the conjugate Brønsted–Lewis superacid HF? SbF₅, primarily by solvolytic or reductive carbonylations. Thermally stable salts are formed with the fluoroantimonate(V ) ions [SbF₆]^? and [Sb₂F₁₁]^?. The salts are characterised by analytical, structural, spectroscopic and computational methods. Most homoleptic carbonyl cations have very regular geometries, comensurate with their d‐electron configurations: linear (d¹⁰), square planar (d⁸) or octahedral(d⁶). The cations with metals in oxidation states of +2 or +3 are termed “superelectrophilic”. Extended molecular structures form by significant interionic C? F contacts with electrophilic carbon as acceptor. To account for all experimental observations, a conceptually simple synergetic bonding model is proposed. An outlook at anticipated future developments based on very recent results is provided.     

JO2F3, seine Struktur und F-Ionen-Akzeptor-Eigenschaften

IO₂F₃, originally assumed to have a trigonal bipyramidal structure, is polymeric. Mass spectra confirm the existence of molecules with molecular weights up to three times the formula weight. Chemically, IO₂F₃ is a strong Lewis acid and fluorine ion acceptor, thus forming the anion IO₂F₄ ^?. With SbF₅ it forms a further polymeric compound (IO₂F₃·SbF₅) _n .¹⁹F-NMR, mass, IR and Raman spectra confirm the proposed structures.     

Homoleptic Metal Carbonyl Cations of the Electron-Rich Metals: Their Generation in Superacid Media Together with Their Spectroscopic and Structural Characterization

Homoleptic carbonyl cations of the electron-rich metals in Groups 8 through 12 are the newest members of the large family of transition metal carbonyls. They can be distinguished from typical metal carbonyl complexes in several respects. Their synthesis entails carbonylation of metal salts in such superacids as fluorosulfuric acid and “magic acid” HSO₃F? SbF₅. Thermally stable salts with [Sb₂F₁₁]^? as counterion are obtained with antimony pentafluoride as reaction medium. Both the [Sb₂F₁₁]^? anion and superacid reaction media have previously found little application in the organometallic chemistry of d-block elements. Also unprecedented in metal carbonyl chemistry are the coordination geometries with coordination numbers 4 (square-planar coordination) and 2 (linear coordination) for the cation. Formal oxidation states of the metals, and the charges of the complex cations, extend from + 1 to +3: thus CO is largely σ-bonded to the metal, and the CO bond is strongly polarized. Minimal metal → CO π-backbonding and a positive partial charge on carbon are manifested in long M? C bonds, short C? O bonds, high frequencies for C? O stretching vibrations (up to 2300 cm^?1), and small ¹³C NMR chemical shifts (up to δ_c, = 121). Prominent examples of these unusual homoleptic carbonyl cations, which were recently the subject of a Highlight in this journal, include the first carbonyl cation of a p-block metal [Hg(CO)₂]²⁺, the first trivalent carbonyl cation [Ir(CO)₆]³⁺, and the first multiply charged carbonyl cation of a 3d metal [Fe(CO)₆]²⁺. In this overview we propose to (a) outline the historical origins of cationic metal carbonyls and their methods of synthesis; (b) present a summary of the general field of carbonyl cations, which has developed over a yery short period of time; (c) discuss the structural and spectroscopic characteritics of metal–CO bonding; (d) discuss the special significance associated with reaction media and the [Sb₂F₁₁]^? anion; and (e) point to the most recent results and anticipated future developments.     

Protonated Ethylene Carbonate: A Highly Resonance-Stabilized Cation

Salts containing the monoprotonated ethylene carbonate species of were obtained by reacting it with the superacidic systems XF/MF₅ (X=H, D; M=Sb, As). The salts in terms of [C₃H₅O₃]⁺[SbF₆]⁻, [C₃H₅O₃]⁺[AsF₆]⁻ and [C₃H₄DO₃]⁺[AsF₆]⁻ were characterized by low-temperature infrared and Raman spectroscopy. In order to generate the diprotonated species of ethylene carbonate, an excess of Lewis acid was used. However, this only led to the formation of [C₃H₅O₃]⁺[Sb₂F₁₁]⁻, which was characterized by a single-crystal X-ray structure analysis. Quantum chemical calculations on the B3LYP/aug-cc-PVTZ level of theory were carried out for the [C₃H₅O₃]⁺ cation and the results were compared with the experimental data. A Natural Bond Orbital (NBO) analysis revealed sp² hybridization of each atom belonging to the CO₃ moiety, thus containing a remarkably delocalized 6π-electron system. The delocalization is confirmed by a ¹³C NMR-spectroscopic study of [C₃H₅O₃]⁺[SbF₆]⁻.     

Chemical Bonding in Homoleptic Carbonyl Cations [M{Fe(CO)5}2]+ (M=Cu,Ag, Au)

Syntheses of the copper and gold complexes [Cu{Fe(CO)₅}₂][SbF₆] and [Au{Fe(CO)₅}₂][HOB{3,5-(CF₃)₂C₆H₃}₃] containing the homoleptic carbonyl cations [M{Fe(CO)₅}₂]⁺ (M=Cu, Au) are reported. Structural data of the rare, trimetallic Cu₂Fe, Ag₂Fe and Au₂Fe complexes [Cu{Fe(CO)₅}₂][SbF₆], [Ag{Fe(CO)₅}₂][SbF₆] and [Au{Fe(CO)₅}₂][HOB{3,5-(CF₃)₂C₆H₃}₃] are also given. The silver and gold cations [M{Fe(CO)₅}₂]⁺ (M=Ag, Au) possess a nearly linear Fe-M-Fe’ moiety but the Fe-Cu-Fe’ in [Cu{Fe(CO)₅}₂][SbF₆] exhibits a significant bending angle of 147° due to the strong interaction with the [SbF₆]⁻ anion. The Fe(CO)₅ ligands adopt a distorted square-pyramidal geometry in the cations [M{Fe(CO)₅}₂]⁺, with the basal CO groups inclined towards M. The geometry optimization with DFT methods of the cations [M{Fe(CO)₅}₂]⁺ (M=Cu, Ag, Au) gives equilibrium structures with linear Fe-M-Fe’ fragments and D₂ symmetry for the copper and silver cations and D_4d symmetry for the gold cation. There is nearly free rotation of the Fe(CO)₅ ligands around the Fe-M-Fe’ axis. The calculated bond dissociation energies for the loss of both Fe(CO)₅ ligands from the cations [M{Fe(CO)₅}₂]⁺ show the order M=Au (D_e=137.2 kcal mol⁻¹)>Cu (D_e=109.0 kcal mol⁻¹)>Ag (D_e=92.4 kcal mol⁻¹). The QTAIM analysis shows bond paths and bond critical points for the M−Fe linkage but not between M and the CO ligands. The EDA-NOCV calculations suggest that the [Fe(CO)₅]→M⁺←[Fe(CO)₅] donation is significantly stronger than the [Fe(CO)₅]←M⁺→[Fe(CO)₅] backdonation. Inspection of the pairwise orbital interactions identifies four contributions for the charge donation of the Fe(CO)₅ ligands into the vacant (n)s and (n)p AOs of M⁺ and five components for the backdonation from the occupied (n-1)d AOs of M⁺ into vacant ligand orbitals.     

Investigation of Bis(Perfluoro-tert-Butoxy) Halogenates(I/III)

A systematic study of halogenate(I/III) anions with polyatomic ligands is presented. The bis(perfluoro-tert-butoxy) halogenates(I) [X(OC₄F₉)₂]⁻, X=Cl, Br, I, of chlorine, bromine, and iodine are prepared as their tetraethylammonium salts and characterized with IR, Raman, and NMR spectroscopic methods, as well as single-crystal X-ray diffraction analyses. Spectroscopical data are supported by quantum-chemical calculations. Additionally, the bonding situation of the species in question are analyzed and discussed. Furthermore, the oxidation to the corresponding halogenate(III) derivatives was studied. For [Br(OC₄F₉)₂]⁻, oxidation with elemental fluorine gave [BrF₂(OC₄F₉)₂]⁻. Iodide was directly oxidized by ClOC₄F₉ to the I^III species [I(OC₄F₉)₄]⁻, which is a surprisingly inert anion that might be used as a weakly coordinating anion (WCA) in the future. For [Cl(OC₄F₉)₂]⁻, the decomposition products of the synthetic approaches towards a chlorine(III) system were analyzed.     

Diaryldichalcogenide radical cations

One-electron oxidation of two series of diaryldichalcogenides (C₆F₅E)₂ (13a–c) and (2,6-Mes₂C₆H₃E)₂ (16a–c) was studied (E = S, Se, Te). The reaction of 13a and 13b with AsF₅ and SbF₅ gave rise to the formation of thermally unstable radical cations [(C₆F₅S)₂]˙⁺ (14a) and [(C₆F₅Se)₂]˙⁺ (14b) that were isolated as [Sb₂F₁₁]^– and [As₂F₁₁]^– salts, respectively. The reaction of 13c with AsF₅ afforded only the product of a Te–C bond cleavage, namely the previously known dication [Te₄]²⁺ that was isolated as [AsF₆]^– salt. The reaction of (2,6-Mes₂C₆H₃E)₂ (16a–c) with [NO][SbF₆] provided the corresponding radical cations [(2,6-Mes₂C₆H₃E)₂]˙⁺ (17a–c; E = S, Se, Te) in the form of thermally stable [SbF₆]^– salts in nearly quantitative yields. The electronic and structural properties of these radical cations were probed by X-ray diffraction analysis, EPR spectroscopy, and density functional theory calculations and other methods.     

Synthesis and crystal structure of new sodium oxothiocyanofluoroantimonate(III) Na2Sb5F9O3(NCS)2

Na₂Sb₅F₉O₃(NCS)₂, a new complex, has been synthesized from NaSCN and SbF₃ aqueous solutions and studied by chemical, X-ray diffraction, and thermal analyses and IR, ^121,123Sb NQR, and ¹⁹F NMR spectroscopy. Its layered structure (triclinic symmetry system, a = 6.9998(1) Å, b = 9.4180(1) Å, c = 13.1094(2) Å, α = 74.815(1)°, β = 78.188(1)°, γ = 82.779(1)°, Z = 2, space group P $\bar 1$ ) is built of Na⁺ cations and [Sb₁₀F₁₈O₆(NCS)₄]^4? decanuclear complex anions that consist of two [Sb₅F₉O₃(NCS)₂]^2? pentanuclear complex anions linked by two weak Sb-F ionic bonds (2.529(2) Å). Decanuclear complex anions are linked into layers by secondary Sb…F bonds and Na-F bonds. Van der Waals interactions link these layers into a framework. The complex is stable up to 200°C.     

Zur Kristallstruktur von Ba3Al2F12

Concerning the Crystal Structure of Ba₃Al₂F₁₂ Preparing BaMnAlF₇ we obtained single crystals of Ba₃Al₂F₁₂ as a by‐product (a = 1020.3(2), b = 988.5(1), c = 952.2(1) pm, space group Pnnm, Z = 4). The redetermination confirmed the structure already known, but improved the results (R₁′ = 0.028 and wR₂ = 0.06 for 1908 and 2717 reflections, resp.). An interpretation is given for the relation of distances within the tetrameric anion [Al₄F₂₀]^8— (average Al—F: 180, 1 pm). The construction of the cationic frame [Ba₃F₂]⁴⁺ is discussed.     

Darstellung,spektroskopische Charakterisierung und Kristallstruktur von (CF3)2C(F)OH2+Sb2F11–

Preparation, Spectroscopic Characterization, and Crystal Structure of (CF₃)₂C(F)OH₂⁺Sb₂F₁₁^– Hexafluoroacetone, (CF₃)₂CO, reacts at –78 °C with the superacid HF/SbF₅ under formation of the primary oxonium salt, (CF₃)₂C(F)OH₂⁺Sb₂F₁₁^–, which is characterized by vibrational spectroscopy and NMR spectra. The salt crystallizes in the triclinic space group P1 with a = 817.9(1), b = 989.0(1), c = 1003.8(1) pm and 2 formula units per unit cell.