Phosphaniminato-Komplexe des Antimons. Die Kristallstrukturen von [Sb2Cl5(NPMe3)2][SbCl6] · CH3CN und [SbCl(NPPh3)]2[SbCl6]2 · 6 CH3CN

Phosphorane Iminato Complexes of Antimony. The Crystal Structures of [Sb₂Cl₅(NPMe₃)₂][SbCl₆] · CH₃CN and [SbCl(NPPh₃)]₂[SbCl₆]₂ · 6 CH₃CN The title compounds are formed by reaction of antimony pentachloride in acetonitrile solution with the phosphorane iminato complexes SbCl₂(NPMe₃) and SbCl₂(NPPh₃), respectively, which themselves are synthesized by reaction of antimony trichloride with Me₃SiNPR₃ (R = Me, Ph). The complexionic compounds are characterized by ¹²¹Sb Mössbauer spectroscopy and by crystal structure determinations. [Sb₂Cl₅(NPMe₃)₂][SbCl₆] · CH₃CN: Space group P4₁, Z = 4, 3 698 observed unique reflections, R = 0.022. Lattice dimensions at ?60°C: a = b = 1 056.0(1), c = 2 709.6(2) pm. The structure consists of SbCl₆^? ions and cations [Sb₂Cl₅(NPMe₃)₂(CH₃CN)]⁺, in which one Sb^III atom and one Sb^V atom are bridged by the N atoms of the phosphorane iminato ligands. [SbCl(NPPh₃)]₂[SbCl₆]₂ · 6 CH₃CN: Space group P1 , Z = 2, 5 958 observed unique reflections, R = 0.033. Lattice dimensions at ?60°C: a = 989.4(11), b = 1 273(1), c = 1 396(1) pm, α = 78.33(7), β = 77.27(8)°, γ = 86.62(8)°. The structure consists of SbCl₆^? ions and centrosymmetric cations [SbCl(NPPh₃)(CH₃CN)₂]₂²⁺, in which the antimony atoms are bridged by the N atoms of the phosphorane iminato ligands.     

121Sb-Mössbauer-Spektren von Antimon(V)-Verbindungen. II

¹²¹Sb Mössbauer Spectra of Antimony (V) Compounds. II The Mössbauer resonance effect of ¹²¹Sb has been studied at 4.2 K in a series of 11 antimony(V) compounds which are in most cases bridged. Isomer shift and quadrupole splitting variations are considered in the light of results of X-ray and vibrational spectroscopy. Preparation and the vibrational spectra of [NMe₄][SbCl₄(n₃)₂] are described. Within the limitations of available structural data related tin compounds are compared with those of corresponding ¹¹⁹Sn Mössbauer spectra.     

Oxidative Addition von N‐Chlortriphenylphosphanimin an Phosphortrichlorid und Antimontrichlorid. Kristallstrukturen von (Cl3PNPPh3)2[PCl6][ClHCl],[SbCl4(HNPPh3)2][SbCl6] und [Sb(NPPh3)4][SbCl6]

Oxidative Addition of N‐chlorotriphenylphosphoraneimine onto Phosphorus(III) Chloride and Antimony(III) Chloride. Crystal Structures of (Cl₃PNPPh₃)₂[PCl₆][ClHCl], [SbCl₄(HNPPh₃)₂][SbCl₆], and [Sb(NPPh₃)₄][SbCl₆] Phosphorus(III) chloride reacts with N‐chlorotriphenylphosphoraneimine, ClNPPh₃, in CH₂Cl₂ solution strongly exothermically via oxidative addition to give (Cl₃PNPPh₃)₂[PCl₆][ClHCl] ( 1 ). As a by‐product, Ph₃PNP(O)Cl₂ can be obtained, which is formed from PCl₃ and ClNPPh₃ in the presence of POCl₃. In contrast to these results, antimony(III) chloride reacts with ClNPPh₃ in CH₂Cl₂ solution to give a mixture of the phosphoraneimine complex [SbCl₄(HNPPh₃)₂][SbCl₆] ( 2 ) and the phosphoraneiminato complex [Sb(NPPh₃)₄][SbCl₆] ( 3 ). The complexes 1 ‐ 3 were characterized by IR spectroscopy and by single crystal X‐ray determinations. 1 : Space group C2/c, Z = 4, lattice dimensions at 193 K: a = 3282.0(2), b = 798.7(1), c = 1926.1(2) pm, β = 107.96(1)°, R₁ = 0.0302. 1 contains [Cl₃PNPPh₃]⁺ cations with PN bond lengths of 152.5(2) and 160.9(2) pm, and a PNP bond angle of 140.5(1)°. 2 ·CH₂Cl₂: Space group , Z = 2, lattice dimensions at 193 K: a = 1031.2(1), b = 1448.3(2), c = 1811,4(2) pm, α = 70.96(1)°, β = 87.67(1)°, γ = 75.37(1)°, R₁ = 0.0713. 2 ·CH₂Cl₂ contains cations [SbCl₄(HNPPh₃)₂]⁺ with octahedrally coordinated Sb atom and the HNPPh₃ ligand molecules being in trans‐position. Sb–N bond lengths are 207.6(6) and 209.3(6) pm, PN bond lengths 162.3(7) and 160.8(7), which approximately corresponds with double bonds. 3 ·0.5CH₂Cl₂: Space group P4/n, Z = 2, lattice dimensions at 193 K: a = b = 1678.8(1), c = 1244.3(1) pm, R₁ = 0.0618. 3 ·0.5CH₂Cl₂ contains [Sb(NPPh₃)₄]⁺ cations with tetrahedrally coordinated Sb atom and short Sb–N bond lengths of 193.7(6) pm. The PN distances of the phosphoraneiminato ligands, (NPPh₃)^? with 156.5(6) pm, correspond with double bonds, the SbNP bond angles are 130.6(3)°.     

Die Kristallstruktur,das Raman- und das 121Sb-Mößbauer-Spektrum des Antimonfluoridchlorids (SbF1+sCl4−s)4 mit s = 0,6

Crystal Structure, Raman and ¹²¹Sb-Mössbauer Spectrum of Antimony Fluoride Chloride (SbF_1+sCl_4?s)₄ with s = 0.6 The title compound was obtained from a 1:1 reaction mixture of SbF₅ and SbCl₅ by vacuum sublimation. It crystallizes in the tetragonal space group I4 with two tetrameric molecules per unit cell; the lattice constants are a = 1 294 and c = 750 pm. The crystal structure was determined with X-ray diffraction data and refined to a reliability index of R = 0.036. As in (SbFCl₄)₄ and (SbF₂Cl₃)₄, the molecule has a flourine-bridged ring structure, the axial positions on one side of the ring being occupied statistically by fluorine and chlorine. Raman spectra show that the structures in the solid, in the melt and in solution differ from each other. The ¹²¹Sb-Mössbauer spectrum is discussed.     

Synthese,Kristallstruktur und 121Sb-Mößbauer-Spektrum von [SbCl2(18-Krone-6)]+SbCl6−

Synthesis, Crystal Structure, and ¹²Sb-Mössbauer Spectrum of [SbCl₂(18-Crown-6)]⁺SbCl₆^? The title compound, which has been prepared by the reaction of antimony trichloride and antimony pentachloride in the presence of 18-crown-6 in acetonitrile solution, is characterized by its ¹²¹Sb-Mössbauer spectrum and by an X-ray structure determination. Space group P2₁, Z = 2, 2439 observed unique reflections, R = 0.045, wR = 0.043. Lattice dimensions at ?80°C: a = 780.6(7), b = 1297.5(9), c = 1 278.5(10) pm, β = 100.56(7)°. The structure of [SbCl₂(18-crown-6)]⁺SbCl₆^? contains cations in which the antimony atom in the first coordination sphere is surrounded in a ?-trigonal-bipyramidal fashion by two oxygen atoms of the crown ether in axial position as well as in the equatorial position by the two chlorine atoms and the lone electron pair.     

[Sb(12-Krone-4)2(CH3CN)][SbCl6]3 und [Bi(12-Krone-4)2(CH3CN)][SbCl6]3, die ersten Trikationen von Antimon(III) und Bismut(III)

[Sb(12-Crown-4)₂(CH₃CN)][SbCl₆]₃ and [Bi(12-Crown-4)₂(CH₃CN)][SbCl₆]₃, first Trications of Antimony(III) and Bismuth(III) The crown ether complexes [M(12-crown-4)₂(CH₃CN)][SbCl₆]₃ with M = Sb and Bi are formed by the reaction of antimony trichloride and bismuth trichloride, respectively, with antimony pentachloride in acetonitrile solution in the presence of 12-crown-4. They form colourless, moisture sensitive crystals, which were characterized by X-ray structure determinations and by IR spectroscopy. The complex with M = Sb was also characterized by ¹²¹Sb Mössbauer spectroscopy. Both complexes crystallize isotypically in the orthorhombic space group Pbcn with four formula units per unit cell. M = Sb: 3 483 observed unique reflections, R = 0.038. M = Bi: 2 958 observed unique reflections, R = 0.036. The compounds consist of SbCl₆^? ions and trications [M(12-crown-4)₂(CH₃CN)]³⁺, in which the M³⁺ ions are ninefold coordinated by the eight oxygen atoms of the crown ether molecules and by the nitrogen atom of the acetonitrile molecule. The lone pair of the M³⁺ ions has no steric effect.     

Beiträge zum 121Sb-Mößbauer-Effekt. VIII. Schwingungsspektrum und 121Sb-Mößbauer-Spektrum von P2O3Cl4 · 2 SbCl5 Die. Kristallstruktur von [SbCl4(O2PCl2)]2

On ¹²¹Sb-Mössbauer Effect. VIII. Vibrational Spectrum and ¹²¹Sb-Mössbauer Spectrum of P₂O₃Cl₄ · 2 SbCl₅. Crystal Structure of [SbCl₄(O₂PCl₂)]₂ The donor-acceptor complex P₂O₃Cl₄ · 2 SbCl₅ is prepared from P₂O₃Cl₄ and excess SbCl₅ in carbon tetrachloride at ?20°C. According to the vibrational spectrum and the ¹²¹Sb-Mössbauer parameters the SbCl₅ molecules are bonded to the terminal O atoms of P₂O₃Cl₄. Thermolysis of the adduct yields the dichloro phosphate [SbCl₄(O₂PCl₂)]₂ which has been discussed earlier. The crystal structure of the dimer was determined by means of X-ray diffraction; it crystallizes monoclinic in the space group P2₁/c with two dimeric molecules per unit cell (1843 independent, observed reflexions, R = 4.0%). The cell dimensions are a = 857 pm, b = 1144 pm, c = 1091 pm; β = 108.6°. In the molecule two SbCl₄ units are linked by the O atoms of the dichlorophosphate groups to form a centrosymmetric eightmembered ring with chair conformation.     

Schwingungsspektroskopische Untersuchungen an Trimethylphosphonium-Kationen (CH3)3PX+ (X = H,D) und Kristallstrukturen von (CH3)3PD+SbCl6− und (CH3)3PCl+SbCl6−

Vibrational Spectra of Trimethylphosphonium Cations (CH₃)₃PX⁺ (X = H, D) and Crystal Structures of (CH₃)₃PD⁺SbCl₆^? and (CH₃)₃PCl⁺SbCl₆^? The trimethylphosphonium salts (CH₃)₃PX⁺SbCl₆^? (X = H, D) and (CH₃)₃PH⁺MF₆^? (M = As, Sb) are prepared and characterized by vibrational and NMR spectroscopy (¹H, ³¹P, ¹³C). In addition the crystal structures of (CH₃)₃PD⁺SbCl₆^? and (CH₃)₃PCl⁺SbCl₆^? are reported. (CH₃)₃PD⁺SbCl₆^? crystallizes in the orthorhombic space group Pnma with a = 1555(1) pm, b = 753.1(8) pm, c = 1166(1) pm Z = 4. (CH₃)₃PCl⁺SbCl₆^? crystallizes triclinic in the space group P1 with a = 704.6(4) pm, b = 729.5(3) pm, c = 1391.1(7) pm, α = 89.57(4)°, b? = 88.04(4)°, γ = 74.98(4)° and Z = 2.     

Darstellung von μ-Schwefeldisulfoniumsalzen [(CH3)2S?Sx?S(CH3)2]2+2A− (x = 1–3, A− = AsF6−, SbF6−, SbCl6−). Über die Analogie im Reaktionsverhalten zwischen Sulfanen und Sulfoniumsalzen

Preparation of μ-Sulfurdisulfonium Salts [(CH₃)₂S? S_x? S(CH₃)₂]²⁺2A^? (x = 1–3, A^? = AsF₆^?, SbF₆^?, SbCl₆^?). On the Analogy of the Reactivity of Sulfanes and Sulfonium Salts The preparation of the μ-sulfurdisulfonium salts [(CH₃)₂S? S_x? S(CH₃)₂]²⁺(A^?)₂ with x = 1–3 and A^? = AsF₆^?, SbF₆^?, SbCl₆^? is reported. The salts are formed by reaction of (CH₃)₂SH⁺A^? and (CH₃)₂SSH⁺A^? with SCl₂ and S₂Cl₂, resp. They are characterized by vibrational spectroscopic measurements. [(CH₃)₂S? S₂? S(CH₃)₂]²⁺(SbF₆^?)₂ crystallizes in the space group C2/c with a = 1 884.5(7) pm, b = 1 302.8(5) pm, c = 1 477.2(5) pm, β = 98.62(3)° und Z = 8.     

{ReCl2(NO)2[Sb(C6H5)3]2}; Synthese,Kristallstruktur, Infrarot- und 121Sb-Mößbauer-Spektrum

{ReCl₂(NO)₂[Sb(C₆H₅)₃]₂}; Preparation, Crystal Structure, Infrared and ¹²¹Sb Mössbauer Spectrum The title compound yields from treatment of ReCl₃(NO)₂ with excess Sb(C₆H₅)₃ in a dichloromethane suspension forming green crystals. The structure of {ReCl₂(NO)₂[Sb(C₆H₅)₃]₂} was solved by X-ray methods; the complex crystallizes in the triclinic space group P1 with three formula units per unit cell (9522 undependent, observed reflexions, R = 5.0%). The lattice constants are a = 1251, b = 1414, c = 1671 pm, α = 66.2, β = 83.0, γ = 89.1°. The Rhenium atom is coordinated octahedrally by two NO groups, two Cl atoms, which are in cis-position to one another and two antimony atoms of the SbPh₃ ligands, which are in trans positions. The NO and Cl ligands are statistically disordered in the equatorial plane. The I.R. spectrum as well as the ¹²¹Sb-Mössbauer spectrum, the latter obtained at 4.2 K, are recorded.     

Darstellung,Mössbauer- und Schwingungsspektren der Komplexe [SnCl4F]⊖, [SnCl4(NCS)]⊖ und [SnCl4(NCS)2]2⊖

Preparation, Mössbauer and Vibrational Spectra of the Complexes [SnCl₄F]^?, [SnCl₄(NCS)]^?, and [SnCl₄(NCS)₂]^2? N(CH₂)₄F and N(CH₂)₄SCN react in liquid SO₂ with SnCl₄ yielding the adducts [N(CH₃)₄][SnCl₄F] (I), [N(CH₃)₄][SnCl₄(NCS)] (II) and [N(CH₃)₄]₂[SnCl₄(NCS)₂] (III).respectively. Mössbauer and vibrational spectra indicate for the anion of I a fluoro-bridged species, which is probably tetrameric like the isoelectronic SbCl₄F. For II dimeric moieties are proposed with bridging S-atoms, while [SnCl₄(NCS)₂]^2? has an octahedral structure with N-bonded isothiocyanate groups in the trans-positions.     

Über die Reaktion von HCl im System HF/SbF5 und die Kristallstruktur von SbCl3F2

On the Reaction of HCl with HF/SbF₅ and the Crystal Structure of SbCl₃F₂ The reaction of HCl in HF/SbF₅ solution at ?78°C yields H₂F⁺SbClF₅^?. At ?40°C formation of SbCl₃F₂ was observed, which crystallizes in the tetragonal space group I-4 with a = 1 281.6(5) pm, c = 758.1(6) pm with 8 formula units per unit cell. The structure contains cis-fluorine-bridged tetramers, in which Sb has a distorted octahedral coordination.     

Oxo-Phosphaniminato-Komplexe von Molybdän und Wolfram. Die Kristallstrukturen von [Mo(O)2(NPPh3)2] und [WO(NPPh3)3]2[W6O19]

Oxo-phosphoraneiminato Complexes of Molybdenum and Tungsten. Crystal Structures of [Mo(O)₂(NPPh₃)₂] and [WO(NPPh₃)₃]₂[W₆O₁₉] The dioxo-phosphoraneiminato complexes [Mo(O)₂(NPPh₃)₂] ( 1 ) and [W(O)₂(NPPh₃)₂] ( 2 ) originate from hydrolysis of the nitrido complexes [MN(NPPh₃)₃] (M = Mo, W). They form colourless crystals, which are characterized by IR and NMR spectroscopy as well as by mass spectrometry. According to the crystal structure analysis of 1 (space group Fdd2, Z = 8; lattice dimensions at –83 °C: a = 1953.3(1), b = 3275.8(3), c = 953.4(1) pm) there are monomeric molecules with tetrahedrally coordinated molybdenum atoms. The distances MoO of 171.2 pm and MoN of 185.9 pm correspond to double bonds. In dichloromethane solution 2 undergoes further hydrolysis with colourless crystals of [WO(NPPh₃)₃]₂[W₆O₁₉] ( 3 ) originating, which are characterized crystallographically (space group Pbcn, Z = 4; lattice dimensions at –50 °C: a = 3225.1(6), b = 1803.6(3), c = 1811.9(3) pm). 3 consists of cations [WO(NPPh₃)₃]⁺ with tetrahedrally coordinated tungsten atoms and of the known [W₆O₁₉]^2– anions. The tungsten atoms of the cations show distances WO of 171.8 pm and WN of 182 pm which correspond to double bonds as in 1 .     

Kristallstruktur und Schwingungsspektrum von Tris-trichlorophosphazeno-carbenium-hexachloroantimont [C(N  PCl3)3]+SbCl6−

Crystal Structure and Vibrational Spectrum of Tris-trichlorophosphazeno-carbenium-hexachloroantimonate [C(N?PCl₃)₃]⁺SbCl₆^? [C(N?PCl₃)₃]SbCl₆ crystallizes in the space group P1 with the lattice constants a = 903 b = 1046, c = 1307 pm and α = 94.8, β = 88.3, γ = 103.8°. Using X- ray diffraction data, the crystal structure was determined and refined to a residual index of 0.027. The structure consists of octahedral SbCl₆^? ions and [C(N?PCl₃)₃]⁺ ions having approximately C_3h symmetry; the atoms C, N, P, and one Cl per PCl₃ group lie approximately in a plane. The i. R. and Raman spectrum was registered and assigned.     

Cs[Yb(NPPh3)4] – ein homoleptischer Phosphaniminato‐Komplex des Ytterbiums

Cs[Yb(NPPh₃)₄] – a Homoleptic Phosphoraneiminato Complex of Ytterbium Cesium tetrakis(phosphoraneiminato)ytterbate, Cs[Yb(NPPh₃)₄] ( 1 ) has been prepared by the reaction of the dimeric complex [Yb(NPPh₃)₃]₂ with CsNPPh₃ in thf solution. 1 crystallizes from thf solution to give colourless moisture sensitive crystals which contain three molecules thf per asymmetric unit. According to the crystal structure determination 1 forms a dimeric ion ensemble [Cs{Yb(NPPh₃)₄}]₂ in which the Cs⁺ ions connect the [Yb(NPPh₃)₄]^– ions via Cs…N bridges. The ytterbium atoms are distorted tetrahedrally coordinated by the nitrogen atoms of the phosphoraneiminato ligands (NPPh₃^–) with short Yb–N‐bond lengths between 212.1 and 221.9(8) pm. The included thf molecules are without bonding contacts with the complex. [Cs{Yb(NPPh₃)₄}]₂ · 6 thf: Space group P 1, Z = 2, lattice dimensions at 193 K: a = 1837.2(2), b = 2041.5(2), c = 2095.8(2) pm, α = 79.953(13)°, β = 79.364(11)°, γ = 88.239(12)°, R = 0.0625.     

121Sb-Mössbauer-Spektren von Antimon(V)-Verbindungen. III

¹²¹Sb Mössbauer Spectra of Antimony (V) Compounds. III The Mössbauer resonance effect of ¹²¹Sb has been studied in the antimony(V) compounds I–VI. Isomer shift and quadrupole splitting variations are considered in the light of results of vibrational spectroscopy and in part of X-ray data. The antimony iodine azides II and IV , respectively, were obtained by reactions of R₃Sb (R = CH₃, C₆H₅) with iodine azide.     

Phosphaniminato-Trichloroselenate(II): Synthese und Kristallstrukturen von [SeCl(NPPh3)2]+SeCl3− und [Me3SiN(H)PMe3]2+[Se2Cl6]2−

Phosphorane Iminato-Trichloroselenates(II): Syntheses and Crystal Structures of [SeCl(NPPh₃)₂]⁺SeCl₃^? and [Me₃SiN(H)PMe₃]₂⁺[Se₂Cl₆]^2? [SeCl(NPPh₃)₂]⁺SeCl₃^? has been synthesized by the reaction of Se₂Cl₂ with Me₃SiNPPh₃ in acetonitrile solution, forming orangered crystals, whereas red crystals of [Me₃SiN(H)PMe₃]₂⁺[Se₂Cl₆]^2? were obtained by the reaction of Me₃SiNPMe₃ with SeOCl₂ in acetonitrile solution. Both complexes were characterized by X-ray structure determinations. [SeCl(NPPh₃)₂]⁺SeCl₃^?: Space group P2₁/n, Z = 4, structure solution with 7 489 observed unique reflections, R = 0.057. Lattice dimensions at ?60°C: a = 1 117.0; b = 2 241, c = 1 407.5 pm, β = 95.61°. In the cation [SeCl(NPPh₃)₂]⁺ the selenium atom is φ-tetrahedrally coordinated by the chlorine atom and by the nitrogen atoms of the phosphorane iminato ligands, whereas the anion SeCl₃^? has a T-shaped structure with φ-trigonal-bipyramidale surrounding of the selenium atom. [Me₃SiN(H)PMe₃]₂⁺[Se₂Cl₆]^2?: Space group P2₁/c, Z = 4, structure solution with 2 093 observed unique reflections, R = 0.080. Lattice dimensions at ?70°C: a = 956, b = 828, c = 1 973 pm, β = 93.80°. The structure consists of [Me₃SiN(H)PMe₃]⁺ ions and planar [Se₂Cl₆]^2? anions, in which the selenium atoms are bridged nearly symmetrically by two chlorine atoms.     

Synthese und Kristallstrukturen der homoleptischen Phosphaniminato‐Kationen [E(NPPh3)3]+ (E = S,Se, Te) mit Iodid und Triiodid als Gegenionen

Synthesis and Crystal Structures of the homoleptic Phosphoraneiminato Cations [E(NPPh₃)₃]⁺ (E = S, Se, Te) with Iodide and Triiodide Counter Ions N‐Iod‐triphenylphosphaneimine, INPPh₃, reacts with the chalcogenes sulfur, selenium and tellurium in boiling tetrahydrofuran to give the phosphoraneiminato complexes [E(NPPh₃)₃]⁺[¹/₂ I₃^–, ¹/₂ I^–] · THF (E = S ( 1 ), E = Se ( 2 )) and [Te(NPPh₃)₃]⁺I₃^– ( 3 ), respectively. The componds form red crystals which are characterized by IR spectroscopy and by crystal structure determinations. The homoleptic cations [E(NPPh₃)₃]⁺ have pyramidal structures with short EN and PN bond lengths, corresponding to double bonds. 1 : Space group Pa 3, Z = 8, lattice dimensions at –80 °C: a = b = c = 2192.9(1) pm, R₁ = 0.0299. 2 : Space group Pa 3, Z = 8, lattice dimensions at –80 °C: a = b = c = 2202.5(1) pm, R₁ = 0.0357. 3 : Space group Pca2₁, Z = 4, lattice dimensions at –90 °C; a = 1075.8(2); b = 1988.8(4); c = 2437.2(3) pm, R₁ = 0.0443.     

Darstellung von CF3SClF+MF6− (M = As,Sb) und Kristallstruktur von CF3SCl2+SbF6−

Preparation of CF₃SClF⁺MF₆^? (M = As, Sb) and Crystal Structure of CF₃SCl₂⁺SbF₆^? CF₃SClF⁺MF₆^? (M = As, Sb) is prepared by oxidative fluorination of CF₃SCl with XeF⁺MF₆^?. The new salt is characterized by IR, Raman and NMR spectra in comparison with CF₃SF₂⁺MF₆^? and CF₃SCl₂⁺MF₆^?. In SO₂ solution CF₃SClF⁺SbF₆^? symmetrizises into CF₃SF₂⁺SbF₆^? and crystalline CF₃SCl₂⁺SbF₆^? with the monoclinic space group P2₁/c with a = 773.5(14) pm, b = 954.8(15) pm, c = 1242.0(18) pm, β = 100.24(8)°, Z = 4.     

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.