- Synthesis and Raman spectra of [Nd (XeF2)n](AsF6)3 (n = 3, 2.5) and crystal structure of [Nd (XeF2)2.5](AsF6)3
-
The reaction between Nd(AsF6)3(solv) and excess of XeF2(solv) in anhydrous HF (aHF) yields compounds of the type [Nd(XeF2)n](AsF6)3 (n = 3, 2.5). The first compound is very soluble in aHF while the latter crystallizes from the saturated solution in aHF. Pink needles [Nd(XeF2)2.5] (AsF6)3 crystallize in the space group C2/m with a = 3463.7(8) pm, b = 586.3(2) pm, c = 1010.7(2) pm, β = 103.53(2)°, V = 1.9955(9) nm3, Z = 4, R1 = 0.0379, wR2 = 0.0910, 5341 reflections collected, 2318 independent reflections. The Nd center is coordinated by a tricapped trigonal prism of nine fluorine atoms. The rectangular faces are capped by three coordinated XeF2 molecules. The regular trigonal prisms are formed by six different edge-bridging AsF6 octahedra, connecting the Nd centers to infinite chains. Two of such chains are interconnected by one of the XeF2 molecules forming a double chain.
- Tramsek,Lork,Mews,Zemva
-
-
Read Online
- Preparation and Characterization of the Adduct UO2F2*AsF5
-
The adduct UO2F2*AsF5 has been prepared as a pale yellow solid by the reaction of UO2F2 with AsF5 in anhydrous hydrogen fluoride.The adduct has been identified by mass balance, chemical analysis, vibrational spectra, X-ray powder diffraction patterns, and thermal analysis.
- Gantar, Darja,Frlec, Boris,Volavsek, Bogdan
-
-
Read Online
- Syntheses, characterization, and computational study of AsF5 adducts with ketones
-
Lewis acid-base adducts between AsF5 and the ketones, acetone, cyclopentanone, and adamantanone, were synthesized from SO2 and CH2Cl2 solutions. These adducts, which contain O—As pnictogen bonding interactions, were found to be stable in solutions at room temperature. Raman and NMR spectroscopy of the solid adducts showed a characteristic decrease in the C=O stretching frequency, as well as dramatic deshielding of the 13C resonance of the carbonyl group upon adduct formation. Fluorine-19 NMR spectroscopy showed the two fluorine environments of the O–AsF5 moiety. Optimization of the gas-phase geometry using DFT calculations yielded geometries with essentially planar CC=OAs moieties. NBO analyses of the adducts and the free ketones show the polarization of the C=O bond upon adduct formation. The lowering of the LUMO energies upon adduct formation is more dramatic than what was found for protonation of ketones and reflects the substantially enhanced electrophilicity of the adducted ketones.
- Stuart, Daniel,Wetmore, Stacey D.,Gerken, Michael
-
-
Read Online
- The Influence of the Counterions [AsF6]– and [GeF6]2– on the Structure of the [ClSO2NH3]+ Cation
-
Chlorosulfonamide reacts in the superacidic solutions HF/GeF4 and HF/AsF5 under the formation of ([ClSO2NH3]+)2[GeF6]2– and [ClSO2NH3]+/sup
- Leitz, Dominik,Stierstorfer, Karin,Morgenstern, Yvonne,Zischka, Florian,Kornath, Andreas J.
-
p. 483 - 488
(2018/05/14)
-
- [Li(XeF2)n](AF6) (A = P, As, Ru, Ir), the first xenon(II) compounds of lithium. Synthesis, Raman spectrum, and crystal structure of [Li(XeF2)3](AsF6)
-
The reactions between compounds of the type MAF6 (M = alkali metal; A = P, As, V, Ru, Ir, Sb, Nb, Ta) and xenon difluoride were studied in anhydrous hydrogen fluoride solvent. The coordination products [M(XeF 2)n]AsF6 were only observed in the case of LiAF6 (A = P, As, Ru, Ir), and the crystal structure of [Li(XeF 2)3]AsF6 was determined (monoclinic space group P21 with a = 6.901(9) A, b = 13.19(2) A, c = 6.91(1) A, β = 91.84(2), and Z = 2). The coordination sphere of lithium is comprised of six F atoms. The compound series was also characterized by Raman spectroscopy.
- Tavcar, Gasper,Zemva, Boris
-
p. 4319 - 4323
(2013/05/22)
-
- On the XeF+/H2O system: Synthesis and characterization of the xenon(II) oxide fluoride cation, FXeOXeFXeF+
-
The reported synthesis of the H2OF+ cation as a product of the oxidative fluorination of H2O by [XeF][PnF 6] (Pn = As, Sb) in HF solution has been reinvestigated. The system exhibits complex equilibria, producin
- Gerken, Michael,Moran, Matthew D.,Mercier, Helene P. A.,Pointner, Bernard E.,Schrobilgen, Gary J.,Hoge, Berthold,Christe, Karl O.,Boatz, Jerry A.
-
p. 13474 - 13489
(2009/12/27)
-
- New Coordination Compounds of Cd(AsF6)2 with HF and XeF2
-
Two new coordination compounds of cadmium with HF and XeF2 as ligands have been synthesized. Solid white [Cd(HF)](AsF6) 2 is obtained from an anhydrous HF (aHF) solution of Cd(AsF 6)2. It crystallizes in a monoclinic P21/c space group with a = 9.4687(14) A, b = 9.2724(11) A, c = 10.5503(18) A, β = 104.887(7)°, and Z = 4. The coordination sphere of Cd consists of 7 + 2 fluorine atoms, which are in a capped trigonal-prismatic arrangement. The reaction between Cd(AsF6)2 and XeF 2 in aHF yields a solid white product at room temperature having the composition [Cd(XeF2)4](AsF6)2 after the excess XeF2 and solvent have been removed under dynamic vacuum. [Cd(XeF2)4](AsF6)2 crystallizes in the orthorhombic space group P21212 1, with a = 8.6482(6) A, b = 13.5555(11) A, c = 16.6312(14) A, and Z = 4. The coordination sphere of Cd consists of eight fluorine atoms, which are at the corners of a trigonal prism with two capped side faces.
- Tavcar, Gasper,Benkic, Primoz,Zemva, Boris
-
p. 1452 - 1457
(2008/10/09)
-
- Syntheses, structures and properties of 1-ethyl-3-methylimidazolium salts of fluorocomplex anions
-
Fluoroacid-base reactions of a room-temperature ionic liquid, 1-ethyl-3-methylimidazolium fluorohydrogenate (EMIm(HF)2.3F, EMIm = 1-ethyl-3-methylimidazolium cation), and Lewis fluoroacids (BF3, PF5, AsF5, NbF5, TaF5 and WF6) give EMIm salts of the corresponding fluorocomplex anions, EMImBF4, EMImPF6, EMImAsF6, EMImNbF6, EMImTaF6 and EMImWF7, respectively. Attempts to prepare EMImVF6 by both the acid-base reaction of EMIm(HF)2.3F with VF5 and the metathesis of EMImCl with KVF6 failed due to the strong oxidizing power of the pentavalent vanadium, whereas EMImSbF6 was successfully prepared only by the metathesis of EMImCl and KSbF6. EMImBF4, EMImSbF6, EMImNbF6, EMImTaF6 and EMImWF7 are liquids at room temperature whereas EMImPF6 and EMImAsF6 melts at around 330 K. Raman spectra of the obtained salts showed the existence of the EMIm cation and corresponding fluorocomplex anions. IR spectroscopy revealed that strong hydrogen bonds are not observed in these salts. EMImAsF6 (mp 326 K) and EMImSbF6 (mp 283 K) are isostructural with the previously reported EMImPF6. The melting point of the hexafluorocomplex EMIm salt decreases with the increase of the size of the anion (PF6- 6- 6- 6- ≈ TaF6-).
- Matsumoto, Kazuhiko,Hagiwara, Rika,Yoshida, Ryuhei,Ito, Yasuhiko,Mazej, Zoran,Benkic, Primoz,Zemva, Boris,Tamada, Osamu,Yoshino, Hideaki,Matsubara, Seijiro
-
p. 144 - 149
(2007/10/03)
-
- Palladium chemistry in anhydrous HF/AsF5 superacid medium
-
Pd metal dissolves in anhydrous HF (aHF) acidified with AsF5 in the presence of F2 at ≈298 K to give a blue-green solution from which green Pd(AsF6)2 can be isolated. The latter was also prepared by the interaction of PdF2 and AsF5 in aHF or by the reaction between PdO and F2 in aHF acidified with AsF 5. Powdered Pd(AsF6)2 slowly loses AsF 5 in a dynamic vacuum. It can therefore be isolated from solution at T 6)2 were prepared by solvothermal synthesis from a Pd/AsF5/F2/aHF mixture at 393 K. Pd(AsF6)2 is triclinic with a = 500.9(5), b = 538.3(5), c = 864.9(9) pm, α = 74.46(3), β = 89.97(4), γ = 62.47(2)° V = 0.1972(3) nm3, and Z = 1, space group P1 (No. 2). The six-coordinate Pd atoms (coordinated with fluorine) are well separated by isolated AsF6 units. In the 2-175 K temperature range Pd(AsF 6)2 follows the Curie-Weiss law with μeff = 3.53 B.M., Tn = 8 K and θp = -13 K. Because of cation-anion interactions, the AsF6- anions deviate from ideal Oh symmetry. The reduced symmetry can be seen in vibrational spectra, where splitting of the anion vibrational modes can be observed. The oxidation of Pd metal or PdO with F2 in neutral aHF yielded Pd 2F6. No reaction was observed between Pd, PdO or Pd 2F6 and AsF5 in aHF. All attempts to prepare PdFAsF6 were unsuccessful. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004.
- Mazej, Zoran,Benkic, Primoz,Tressaud, Alain,Zemva, Boris
-
p. 1827 - 1834
(2007/10/03)
-
- Thermodynamic properties and decomposition of lithium hexafluoroarsenate, LiAsF6
-
The heat capacity of lithium hexafluoroarsenate is determined in the temperature range 50-750 K by adiabatic and differential scanning calorimetry techniques. The thermodynamic properties of LiAsF6 under standard conditions are evaluated: Cp0 (298.15 K)= 162.5 ± 0.3 J/(K mol), S0(298.15 K) = 173.4 ± 0.4 J/(K mol), Φ0(298.15 K) = 81.69 ± 0.20 J/(K mol), and H 0(298.15 K) - H0(0) = 27 340 ± 60 J/mol. The C p(T) curve is found to contain a lambda-type anomaly with a peak at 535.0 ± 0.5 K, which is due to the structural transformation from the low-temperature, rhombohedral phase to the high-temperature, cubic phase. The enthalpy and entropy of this transformation are 5.29 ± 0.27 kJ/mol and 10.30 ± 0.53 J/(K mol), respectively. The thermal decomposition of LiAsF6 is studied. It is found that LiAsF6 decomposes in the range 715-820 K. The heat of decomposition, determined in the range 765-820 K using a sealed crucible and equal to the internal energy change ΔU r(T), is 31.64 ± 0.08 kJ/mol.
- Gavrichev,Sharpataya,Gorbunov,Golushina,Plakhotnik,Goncharova,Gurevich
-
p. 175 - 182
(2008/10/08)
-
- Gold(I) and mercury(II) xenon complexes
-
Noble-gas ligands: For the first time it has been possible to prepare a gold(I) xenon complex ([(F3As)AuXe]+, see picture) and a mercury(II) xenon complex. The syntheses of these compounds start from precursors with weakly coordinated metal ions and take place in a superacid medium.
- Hwang, In-Chul,Seidel, Stefan,Seppelt, Konrad
-
p. 4392 - 4395
(2007/10/03)
-
- The OsO3F+ and μ-F(OsO3F)2+ cations
-
The fluoride ion donor properties of OsO3F2 have been investigated. The salts [OsO3F][AsF6], [OsO3F][HF]2[AsF6], μ-F(OsO3F)2[AsF6], [OsO3F][HF]2[SbF6], and [OsO3F][HF][SbF6] have been prepared by reaction of OsO3F2 with AsF5 and SbF5 in HF solvent and have been characterized in the solid state by Raman spectroscopy. The single-crystal X-ray diffraction studies of [OsO3F][AsF6] (P21/n, a = 7.0001(11) A, b = 11.0620(11) A, c = 8.8629(13) A, β = 92.270(7)°, Z = 4, and R1 = 0.0401 at -126 °C), [OsO3F][SbF6] (P21/c, a = 5.4772(14) A, b = 10.115(3) A, c = 12.234(3) A, β = 99.321(5)°, Z = 4, and R1 = 0.0325 at -173 °C), [OsO3F][HF]2[AsF6] (P21/n, a = 5.1491(9) A, b = 8.129(2) A, c = 19.636(7) A, β = 95.099(7)°, Z = 4, and R1 = 0.0348 at -117 °C), and [OsO3F][HF][SbF6] (Pc, a = 5.244(4) A, b = 9.646(6) A, c = 15.269(10) A, β = 97.154(13)°, Z = 4, and R1 = 0.0558 at -133 °C) have shown that the OsO3F+ cations exhibit strong contacts to the anions and HF solvent molecules giving rise to cyclic, dimeric structures in which the osmium atoms have coordination numbers of 6. The reaction of OsO3F2 with neat SbF5 yielded [OsO3F][Sb3F16], which has been characterized by 19F NMR spectroscopy in SbF5 and SO2CIF solvents and by Raman spectroscopy and single-crystal X-ray diffraction in the solid state (P421m, a = 10.076(6) A, c = 7.585(8) A, Z = 2, and R1 = 0.0858 at -113 °C). The weak fluoride ion basicity of the Sb3F16- anion resulted in an OsO3F+ cation (C3v point symmetry) that is well isolated from the anion and in which the osmium is four-coordinate. The geometrical parameters and vibrational frequencies of OsO3F+, ReO3F, μ-F(OsO3F)2+, [FO3Os - FPnF5)2, and (FO3Os - (HF)2 - FPnF5)2 (Pn = As, Sb) have been calculated using density functional theory methods.
- Gerken, Michael,Dixon, David A.,Schrobilgen, Gary J.
-
p. 259 - 277
(2008/10/08)
-
- Manganese(II) Hexafluoroarsenate: Unusually High Coordination of Manganese(II) in a Fluorine Environment
-
Mn(AsF6)2 was prepared from MnF2 and AsF5 in anhydrous hydrogen fluoride (aHF), and single crystals were grown from the respective solution. The compound crystallizes in the tetragonal space group I42d with a = 750.76(2) pm, c = 1544.44(5) pm, and Z = 4 at 293 K. Due to combined sharing of edges and apexes with AsF6 octahedra. coordination number 8 (Mn-F 4 × 213.0(2) pm and 4 × 241.9(3) pm) is observed for the first time with Mn(II) and fluorine ligands. A second crystalline modification is formed at about 243 K. From susceptibility measurements a magnetic moment of 5.42 μB is derived, but no magnetic ordering is observed above 4 K.
- Borrmann, Horst,Lutar, Karel,Zemva, Boris
-
p. 880 - 882
(2008/10/09)
-
- The oxotrifluoroxenon(VI) cation: X-ray crystal structure of XeOF3+SbF6- and a solution 17O and 129Xe nuclear magnetic resonance study of the 17,18O-enriched XeOF3+ Cation
-
The crystal structure of XeOF3+SbF6- has been determined. The compound crystallized in the triclinic system with a = 8.568 (2) ?, b = 9.760 (2) ?, c = 10.104 (2) ?, α = 109.68 (2)°, β = 92.58 (2)°, γ =104.27 (2)°, V = 763.4 ?3, and Dcalc = 3.829 g cm-3 for Z = 4. The structure has been refined in the space group P1 to a final conventional R factor of 0.045 for 1782 independent reflections with I ≥ 2.5σ(I). The structure consists of XeOF3+SbF6- units with two close contacts between the Xe atom of the cation and F atoms of two SbF6- anions. The isolated XeOF3+ cation is shown to be consistent with the VSEPR rules and to possess an AX4E arrangement of the four bond pair domains and the lone pair domain which give rise to a disphenoid-shaped cation having two longer axial Xe-Fax bonds and an Xe-O bond which is coplanar with the shorter equatorial Xe-Feq bond and xenon. Oxygen-17 and -18 enrichment of the XeOF3+ cation in HF and SbF5 solvents has allowed the determination of the 17O chemical shift and 1J(129Xe-17O), as well as the 16,18O induced secondary isotopic shift in the 129Xe NMR spectrum for the first time.
- Mercier, Hélène P. A.,Sanders, Jeremy C. P.,Schrobilgen, Gary J.,Tsai, Scott S.
-
p. 386 - 393
(2008/10/08)
-
- Preparation of the nitryl salts ON(Cl)F+AsF6-, ON(CF3)F+AsF6-, and HON(CH2)CF3+SbF6- and crystal structure of HON(CH2)CF3+AsF6-
-
The ON(Cl)F+AsF6- and ON(CF3)F+AsF6- salts are prepared by oxidative fluorination of ONCl and ONCF3 with N2F+AsF6-. Methylation of ONCF3 with CH3F and AsF5 gives ON(CH3)CF3+AsF6-, which in the solid state exists as the enol tautomer hydroxylimmonium salt HON(CH2)CF3+AsF6-, triclinic, of space group P1 with a = 5.063 (1) ?, b = 7.757 (3) ?, c = 10.429 (2) ?, α = 86.75 (2)°, β = 89.34 (2)°, and γ = 74.12 (2)°. The framework of the cation is planar, with C-N bond lengths of 147.7 (5) and 127.3 (5) pm and an N-O distance of 137.2(4) pm. The cation and anion have a short H?F contact of 166 (6) pm. An alternative method for the preparation of ONF2+MF6- (M = As, Sb) was found involving the oxidative fluorination of ONF with XeF+MF6-.
- Minkwitz, Rolf,Bernstein, Dirk,Preut, Hans,Sartori, Peter
-
p. 2157 - 2161
(2008/10/08)
-
- Standard molar enthalpies of formation and transition at the temperature 298.15 K and other thermodynamic properties of the crystalline and vitreous forms of arsenic sesquiselenide (As2Se3). Dissociation enthalpies of As-Se bonds
-
Fluorine-combustion calorimetry was used to determine the standard molar enthalpies of formation (at the temperature 298.15 K and with standard pressure po = 101.325 kPa) of the crystalline and vitreous forms of arsenic sesquiselenide.The following results were obtained: ΔfHmo(As2Se3, cr) = -(86.1 +/- 4.1) kJmol-1 and ΔfHmo(As2Se3, vit) = -(58.1 +/- 4.2) kJmol-1.The enthalpy of the transition from the vitreous to the crystalline forms of As2Se3, -(28.0 +/- 3.9) kJmol-1 at 298.15 K, is consistent with two of several published values for th e enthalpy of fusion of the crystalline sesquiselenide.The present results have been combined with enthalpy increments and the standard entropy has been recalculated from the literature to give, for As2Se3(cr) only, ΔfHmo and the standard molar Gibbs energy of formation ΔfGmo as functions of temperature.Mean bond enthalpies have been deduced for As4Se3(g) and As4Se4(g) on the basis of the new ΔfHmo values, and the thermodynamic results are shown to be consistent with a linear structure for As2Se2(g) with a central As-As bond.Bond dissociation enthalpies Dmo(As-X) are given, where X = O, S, Se, and Te.
- O'Hare, P. A. G.,Lewis, Brett M.,Susman, S.,Volin, K. J.
-
p. 1191 - 1206
(2007/10/02)
-
- The standard molar enthalpy of formation at 298.15 K of S2N+AsF6- by fluorine combustion calorimetry
-
The energy of combustion of S2N+AsF6- in high-pressure fluorine has been measured calorimetrically.The only fluorine-containing gases formed in the combustion were SF6 and AsF5; both NF3 and AsF3 were sought, but not detected.The standard molar
- O'Hare, P. A. G.,Awere, Edward G.,Parsons, Simon,Passmore, Jack
-
p. 153 - 158
(2007/10/02)
-
- Thermal behaviour of some new hydrazinium fluorometallates
-
Three new hidrazinium(1+) fluoro complexes, N2H5AsF6, (N2H5)2ZrF6 and (N2H5)2HfF6, were prepared and characterized by means of chemica
- Gantar, D.,Rahten, A.
-
p. 833 - 838
(2008/10/08)
-
- Preparation and Characterization of the Adduct Uranium Pentafluoride-Arsenic-Pentafluoride (1/1)
-
The system UF5-AsF5, UF6-AsF5-UF4, and UF4-AsF5-F2 were studied using anhydrous HF as a solvent.In all cases a dark blue solution results from which blue crystals of composition UF5.AsF5 were isolated at temperatures lower than -30 deg C.At room temperature thermal decomposition of the adduct takes place giving AsF5 vapour, and a solid residue which was identified as β-UF5.
- Gantar, Darja,Frlec, Boris
-
p. 2345 - 2346
(2007/10/02)
-
- INTERACTION BETWEEN URANIUM PENTAFLUORIDE AND THE PENTAFLUORIDES OF VANADIUM, ARSENIC, NIOBIUM, TANTALUM, AND BISMUTH, AND THE TETRAFLUORIDE OF SULPHUR
-
The interaction of UF5 with SF4, SF4O, and some Lewis-acid pentafluorides of various strengths has been studied.In anhydrous HF solutions, SF4 was shown to yield an adduct of composition 3UF5*SF4 in which both ionic and fluorine-bridged species are present.The pentafluorides of arsenic, tantalum, and niobium combine with UF5 to give adducts of composition 1.5 UF5*AsF5, UF5*2TaF5, and UF5*2NbF5, respectively.The arsenic derivative is stable at room temperature only under a pressure of AsF5, whereas the tantalum and niobium adducts decompose at higher temperature forming UF5*TaF5 and UF5*NbF5, respectively.Vibrational spectroscopic study of the pentafluoride adducts of UF5 has shown that they consist of covalent fluorine-bridged species.Uranium pentafluoride is fluorinated at room temperature by VF5 and by BiF5 in anhydrous HF.
- Holloway, John H.,Staunton, Garry M.,Rediess, Klaus,Bougon, Roland,Brown, David
-
p. 2163 - 2166
(2007/10/02)
-
- Coordinatively saturated complex fluoro cations. Synthesis and characterization of ClF6+AsF6- and ClF6+SbF6-
-
The reaction of KrF2 with ClF5 and AsF5 in either ClF5 or anhydrous HF solution produces pure ClF6+AsF6-. The white, crystalline solid is stable up to 110°C under a dynamic vacuum and decomposes at higher temperature to ClF5, F2, and AsF5. X-ray powder diffraction patterns show that ClF6+AsF6- (face-centered cubic; a = 9.47 A?) is isotypic with IF6+AsF6-. The reaction of KrF2 with ClF5 and SbF5 produces ClF6+SbF6-; however, this salt could not be isolated in pure form. 19F NMR and vibrational spectra were recorded for the ClF6+ salts, and an anharmonic general valence force field was computed for ClF6+ by using the observed frequencies and the 35Cl-37Cl isotopic shift of v3 (F1u). General methods for the syntheses of coordinatively saturated complex fluoro cations are compared and discussed.
- Christe, Karl O.,Wilson, William W.,Curtis
-
p. 3056 - 3060
(2008/10/08)
-
- Crystal structure, Raman, and multinuclear magnetic resonance study of FXeN(SO2F)2, an example of xenon-nitrogen bonding
-
The crystal structure of fluoro[imidobis(sulfuryl fluoride)]xenon(II) has been determined at -55 °C from three-dimensional X-ray data. The compound crystallizes in the monoclinic system, space group P21/a, with four molecules in a unit cell of dimensions a = 11.827 (4) A?, b = 6.828 (2) A?, c = 9.467 (3) A?, and β= 112.65 (2)°. The structure was solved by the heavy-atom method and refined by least-squares and Fourier methods to a final R factor of 0.023 for 1721 observed (F > 6σ(F)) reflections. The structure analysis has established the existence of discrete FXeN(SO2F)2 molecules and shows that FXeN(SO2F)2 is Xe-N bonded, representing the first definitive proof for the existence of the Xe-N bond. The xenon atom is approximately linearly coordinated by the nitrogen atom of the imidobis(sulfuryl fluoride) group and a fluorine atom. The angle F-Xe-N is 178.1 (1)°, and the interatomic distances are Xe-N = 2.200 (3) A? and Xe-F = 1.967 (3) A?. Raman spectral data and assignments are also presented for FXeN(SO2F)2, HN(SO2F)2, and Cs+N(SO2F)2-. Solution 15N, 129Xe, and 19F NMR studies of 15N-enriched FXeN(SO2F)2 demonstrate that FXeN(SO2F)2 is also Xe-N bonded in solution. The first example of a directly bonded 129Xe-15N coupling (305 Hz) is also reported.
- Sawyer, Jeffery F.,Schrobilgen, Gary J.,Sutherland, Steven J.
-
p. 4064 - 4072
(2008/10/08)
-
- Novel sulfur-nitrogen-fluorine compounds. Synthesis and properties of SF5NClF, SF5NHF, and FN=SF4 and the molecular structure and vibrational analysis of FN=SF4
-
Pentafluoro(fluorochloroamido)sulfur, SF5NFCl, can be synthesized from NSF3 by low-temperature reaction with ClF, followed by reaction with fluorine. Reduction of SF5NClF with mercury in trifluoroacetic acid forms (fluoroimido)pentafluorosulfur, SF5NHF, in high yield. Dehydrofluorination of SF5NFH with KF results in (fluoroimido)tetrafluorosulfur, FN=SF4. The imine is an unusual pentacoordinate molecule which does not undergo positional exchange of the sulfur fluorines according to 19F NMR. A complete vibrational analysis of FN=SF4 based on Cs symmetry has been carried out and found to be in good agreement with the related molecules OSF4, CH2=SF4, and SF4. The gas-phase structure was determined by joint analysis of electron diffraction and microwave spectroscopic data. The structure contains a relatively long S=N bond, short N-F bond, and a large difference in the nonequivalent axial S-F bonds.
- DesMarteau, Darryl D.,Eysel, Hans H.,Oberhammer, Heinz,Günther, Horst
-
p. 1607 - 1616
(2008/10/08)
-
- Preparation of the XeOTeF5+, FXeFXeOTeF5+, XeF2·BrOF2+, and XeOSO2F+ cations and their study by 129Xe, 125Te, and 19F pulse Fourier transform NMR and Raman spectroscopy
-
The reactions of XeOTeF5+AsF6- with BrF5 have been studied in solution by multinuclear NMR spectroscopy and shown to yield the new fluorine-bridged cations FXeFXeOTeF5+ and XeF2·BrOF2+. The latter has also been isolated at low temperature as its AsF6- salt and characterized in the solid state by Raman spectroscopy. The previously reported XeOTF5+ cation has been more fully characterized by Raman spectroscopy of its AsF6- and Sb2F11- salts and by multinuclear NMR spectroscopy and its solution structure unambiguously established. 129Xe and 19F NMR evidence has also been obtained for the XeOSO2F+ cation by dissolving XeOTeF5+AsF6- in HSO3F.
- Keller, Norman,Schrobilgen, Gary J.
-
p. 2118 - 2129
(2008/10/08)
-
- Composition and Staging in the Graphite-AsF6 System and its Relationship to Graphite-AsF5
-
Interconversion, of graphite-AsF5 intercalates and C12n+AsF6- salts, establishes the equilibrium: 3AsF5 + 2e- 2AsF6- + AsF3, for AsF5 intercalation, and simple staging-stoicheiometry relationships exist for
- McCarron, Eugene M.,Bartlett, Neil
-
p. 404 - 406
(2007/10/02)
-
- Reactivity of transition metal fluorides. II. Uranium hexafluoride
-
Reactions have been studied between uranium hexafluoride and a series of lower fluorides of other elements. The study has also included reaction with a wide range of covalent chlorides. The reactivity of uranium hexafluoride is compared with that of the higher fluorides of d-transition elements, chromium, molybdenum, and tungsten, and considered in the light of uranium as an f-transition element.
- O'Donnell,Stewart,Wilson
-
p. 1438 - 1441
(2008/10/08)
-