7647-19-0

The thermal reactions of a lithiated graphite anode with and without 1.3 M lithium hexafluorophosphate (LiPF6) in a solvent mixture of ethylene carbonate (EC) and ethylmethyl carbonate (EMC) were investigated by means of differential scanning calorimetry (DSC). The products of the thermal decomposition occurring on the lithiated graphite anode were characterized by Fourier transform infrared (FT-IR) analysis. The lithiated graphite anode showed two broad exothermic peaks at 270 and 325 °C, respectively, in the absence of electrolyte. It was demonstrated that the first peak could be assigned to the thermal reactions of PF5 with various linear alkyl carbonates in the solid electrolyte interphase (SEI) and that the second peak was closely related to the thermal decomposition of the polyvinylidene fluoride (PVdF) binder. In the presence of electrolyte, the lithiated graphite anode showed the onset of an additional exothermic peak at 90 °C associated with the thermal decomposition reactions of the SEI layer with the organic solvents.

Three new compounds Ca(HF2)2, Ba4F4(HF2)(PF6)3 and Pb2F2(HF2)(PF6) were obtained in the system metal(II) fluoride and anhydrous HF (aHF) acidified with excessive PF5. The obtained polymeric solids are slightly soluble in aHF and they crystallize out of their aHF solutions. Ca(HF2)2 was prepared by simply dissolving CaF2 in a neutral aHF. It represents the second known compound with homoleptic HF environment of the central atom besides Ba(H3F4)2. The compounds Ba4F4(HF2)(PF6)3 and Pb2F2(HF2)(PF6) represent two additional examples of the formation of a polymeric zigzag ladder or ribbon composed of metal cation and fluoride anion (MF+)n besides PbF(AsF6), the first isolated compound with such zigzag ladder. The obtained new compounds were characterized by X-ray single crystal diffraction method and partly by Raman spectroscopy. Ba4F4(HF2)(PF6)3 crystallizes in a triclinic space group P1 with a=4.5870(2) A, b=8.8327(3) A, c=11.2489(3) A, α=67.758(9)°, β=84.722(12), γ=78.283(12)°, V=413.00(3) A3 at 200 K, Z=1 and R=0.0588. Pb2F2(HF2)(PF6) at 200 K: space group P1, a=4.5722(19) A, b=4.763(2) A, c=8.818(4) A, α=86.967(10)°, β=76.774(10)°, γ=83.230(12)°, V=185.55(14) A3, Z=1 and R=0.0937. Pb2F2(HF2)(PF6) at 293 K: space group P1, a=4.586(2) A, b=4.781(3) A, c=8.831(5) A, α=87.106(13)°, β=76.830(13)°, γ=83.531(11)°, V=187.27(18) A3, Z=1 and R=0.072. Ca(HF2)2 crystallizes in an orthorhombic Fddd space group with a=5.5709(6) A, b=10.1111(9) A, c=10.5945(10) A, V=596.77(10) A3 at 200 K, Z=8 and R=0.028.

A hydrogen fluoride-free and chloro?free method for synthesizing LiPF6 was developed. Employing CaF2 as the direct fluorinating reagent instead of hydrogen fluoride made it much safer and more environment-friendly than conventional methods and reduced the metal residues in product owing to the relatively low-acid reaction conditions less corrosive to equipments. The use of P2O5 as phosphorus source instead of traditionally employed PCl5 significantly reduced the chloro residue in product. Ca(H2PO4)2, the only by-product of the process, could be easily converted into Ca3(PO4)2, a best-selling chemical. The above advantages not only reduce the production costs by ca. 20%, but also significantly improve the product purity. The fluorine-oxygen exchange reaction is a completely new technique for LiPF6 production and may bring about technological revolution in the related industry.

The chemical oxidation and subsequent group transfer activity of the unusual diiron imido complexes Fe(iPrNPPh2)3Fe NR (R = tert-butyl (tBu), 1; adamantyl, 2) was examined. Bulk chemical oxidation of 1 and 2 with Fc[PF6] (Fc = ferrocene) is accompanied by fluoride ion abstraction from PF6- by the iron center trans to the Fe NR functionality, forming F-Fe( iPrNPPh2)3Fe NR (iPr = isopropyl) (R = tBu, 3; adamantyl, 4). Axial halide ligation in 3 and 4 significantly disrupts the Fe-Fe interaction in these complexes, as is evident by the >0.3 A increase in the intermetallic distance in 3 and 4 compared to 1 and 2. Moessbauer spectroscopy suggests that each of the two pseudotetrahedral iron centers in 3 and 4 is best described as FeIII and that one-electron oxidation has occurred at the tris(amido)-ligated iron center. The absence of electron delocalization across the Fe-Fe NR chain in 3 and 4 allows these complexes to readily react with CO and tBuNC to generate the FeIIIFeI complexes F-Fe( iPrNPPh2)3Fe(CO)2 (5) and F-Fe( iPrNPPh2)3Fe(tBuNC)2 (6), respectively. Computational methods are utilized to better understand the electronic structure and reactivity of oxidized complexes 3 and 4.

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.

A non-aqueous electrolyte usable in rechargeable lithium-ion batteries including a solution of LiPF6/carbonate based electrolytes with low concentrations of LiFOP such that the thermal stability is increased compared to a standard lithium battery. A method of making lithium tetrafluorophospahte (LiF4C2O4, LiFOP) including, reacting PF5 with lithium oxalate, recrystallizing DMC/dichloromethane from a 1:1 mixture of to separate LiF4OP from LiPF6 to form a lithium salt. An electric current producing rechargeable Li-ion cell. The rechargeable lithium ion cell includes an anode, a cathode, and a non-aqueous electrolyte comprising a solution of a lithium salt in a non-aqueous organic solvent containing lithium tetrafluorooxalatophosphate (LiPF4(C2O4), LiF4OP).

An electrolyte compound has the formula where p is an integer from 1 to 3 inclusive; and Yp+ is a metal ion, onium species, or proton; j is an integer value between 0 and 4 inclusive; k is an integer between 1 and 3 inclusive; and the sum 2k and j equals 6; Z is independently in each occurrence CR1R2 or C(O); R1 and R2 are independently in each occurrence H, F or CH3. A process for preparing an oxyfluorophosphate is also provided.

A survey is given on the application of elemental fluorine in chemical plants and research centers of Russian Federation.

The present invention relates to oxonium salts having [(Ro)3O]+ cations and sulfonium salts having [(Ro)3S]+ cations, where Ro denotes straight-chain or branched alkyl groups having 1-8 C atoms or phenyl which is unsubstituted or substituted by Ro, ORo, N(Ro)2, CN or halogen, and anions selected from the group of [PFx(CyF2y+1?zHz)6?x]? anions, where 2≦x≦5, 1≦y≦8 and 0≦z≦2y+1, or anions selected from the group of [BFn(CN)4?n]? anions, where n=0, 1 , 2 or 3, or anions selected from the group of [(Rf1SO2)2N]? anions or anions selected from the group of [BFwRf24?w]? anions, to processes for the preparation thereof, and to the use thereof, in particular for the preparation of ionic liquids.

UN-beatable? Laser-ablated uranium atoms activate NF3 and PF3 to form the N≡UF3 and P≡UF3 molecules containing novel terminal nitride and phosphide functional groups. These molecules are identified from matrix infrared spectra and theoretical methods. The N≡UF3 molecule contains the strongest triple bond to uranium in a ternary compound.

From the system MF2/PF5/XeF2/anhydrous hydrogen fluoride (aHF), four compounds [Sr(XeF2)3] (PF6)2, [Pb(XeF2)3]-(PF 6)2, [Sr3(XeF2)10](PF6)6, and [Pb3(XeF2)11](PF6)6 were isolated and characterized by Raman spectroscopy and X-ray single-crystal diffraction. The [M(XeF2)3](PF6)2 (M = Sr, Pb) compounds are isostructural with the previously reported [Sr(XeF 2)3](AsF6)2. The structure of [Sr3(XeF2)10](PF6)6 (space group C2/c, a = 11.778(6) A, b = 12.497-(6) A, c = 34.60(2) A, β = 95.574(4)°, V = 5069(4) A3, Z = 4) contains two crystallographically independent metal centers with a coordination number of 10 and rather unusual coordination spheres in the shape of tetracapped trigonal prisms. The bridging XeF2 molecules and one bridging PF6- anion, which connect the metal centers, form complicated 3D structures. The structure of [Pb3(XeF 2)11](PF6)6 (space group C2/m; a = 13.01(3) A, b = 11.437(4) A, c = 18.487(7) A, β = 104.374(9)°, V = 2665(6) A3, Z = 2) consists of a 3D network of the general formula {[Pb3(XeF2) 10](PF6)6}n and a noncoordinated XeF2 molecule fixed in the crystal structure only by weak electrostatic interactions. This structure also contains two crystallographically independent Pb atoms. One of them possesses a unique homoleptic environment built up by eight F atoms from eight XeF2 molecules in the shape of a cube, whereas the second Pb atom with a coordination number of 9 adopts the shape of a tricapped trigonal prism common for lead compounds. [Pb3(XeF2)11](PF6) 6 and [Sr3(XeF2)10](PF 6)6 are formed when an excess of XeF2 is used during the process of the crystallization of [M(XeF2) 3](PF6)2 from their aHF solutions.

The thermal decomposition of lithium-ion battery electrolytes 1.0 M LiPF6 in one or more carbonate solvents has been investigated. Electrolytes containing diethyl carbonate (DEC), ethylene carbonate (EC), a 1:1 mixture of EC/dimethyl carbonate (DMC), and a 1:1:1 mixture EC/DMC/DEC have been investigated by multinuclear nuclear magnetic spectroscopy, gas chromatography with mass selective detection, and size exclusion chromatography. Thermal decomposition affords products including: carbon dioxide (CO 2), ethylene (CH2CH2), dialkylethers (R 2O), alkyl fluorides (RF), phosphorus oxyfiuoride (OPF3), fluorophosphates [OPF2OR, OPF(OR)2], fluorophosporic acids [OPF2OH, OPF(OH)2], and oligoethylene oxides. The mechanism of decomposition is similar in all LiPF6/carbonate electrolytes. Trace protic impurities lead to generation of OPF2OR, which autocatalytically decomposes LiPF6 and carbonates. The presence of DEC leads to the generation of ethylene, while the presnce of EC leads to the generation of capped oligothylene oxides [OPF2(OCH 2CH2)nF].

The results of a comprehensive study of the thermal stability of the salt LiPF6, using both accelerating rate (ARC) and differential scanning (DSC) calorimetry, are presented. Pressure monitoring during ARC experiments permits also the study of endothermic processes. The origins of apparently inconsistent results and conflicting interpretations in previous reports in the literature are explicated. In a confined volume, LiPF6(s) melts reversibly at 467 K with a heat of melting of 2.0 ± 0.2 kJ mol -1. Reversible decomposition to PF5(g) and LiF(s) commences with melting, but the autogenic development of PF5(g) pressure makes the temperature profile of decomposition a function of volume and sample size. The heat of this reaction at constant volume, ΔU r, as determined by a variety of methods is in the range 60 ± 5 kJ mol-1, and is approximately temperature independent in range 490-580 K.

Enthalpy of formation of lithium hexafluorophosphate was calculated based on the differential scanning calorimetry study of heat capacity and thermal decomposition. It was found that thermal decomposition of LiPF6 proceeds at normal pressure in

Sr5(PO4)3F:Yb3+, a candidate material for gain media, was synthesized by solid-state reaction. Results of chemical analysis, x-ray diffraction, and IR absorption spectroscopy confirm the formation of strontium fluorapatite. Substitution of F- for OH- via fluorination of Sr5(PO4)3OH in hydrofluoric acid or hydrogen fluoride gas leads to the formation of strontium fluoride and phosphorus pentafluoride or oxyfluoride.

The kinetics and mechanism of the gas-phase POF3 + HF reaction is studied by laser and IR spectroscopies. A two-stage model of the reaction is proposed. The interaction of POF3 with HF is shown to yield PF5 and the products of POF3 hydrolysis. The stoichiometric coefficients at POF3, HF, and PF5 in the overall stoichiometric equation of the reaction are determined. The rate and equilibrium constants for individual reaction steps are estimated.

KPO2F2 reacts at room temperature with excess AsF5 in a 1:2 mol ratio. The resulting stable white product was characterized by vibrational and multinuclear NMR spectroscopy in the solid state and SO2 solution, respectively. It is shown that AsF5 neither displaces PO2F from KPO2F2, nor generates PO2+AsF6-, but forms a stable, oxygen-bridged polynuclear [PO2F2?2AsF5]- anion. When pyrolyzed, this anion undergoes a stepwise decomposition to KAsF6, POF3 and AsOF3, followed by the decomposition of KAsF6 to KF and AsF5. While [PO2F2?2AsF5]- is stable in SO2 solution, it decomposes in CD3CN solution to the known CD3CN?AsF5 adduct and [PO2F2?AsF5]- anion. The inability of AsF5 to displace PO2F from its salts confirms that the latter is a very strong Lewis acid which is comparable in strength to AsF5. With PF5 the KPO2F2 salt forms at -78°C the 1:2 adduct K[PO2F2?2PF5], which on warm-up to room temperature loses 1 mol of PF5 to give the 1:1 adduct, K[PO2F2?PF5]. The 1:1 adduct is marginally stable at room temperature and undergoes slow POF3 evolution. An improved synthesis of POF3 from PF5 and P4O10 is reported. Gauthier-Villars.

Me3SnF (1) reacts with many hydrolyzable chlorides to give Me3SnCl and the corresponding fluoride.The formation of PhPF2, (ClCH2)MeSiF2, F2PCH2PF2 and PF5 is described.The reaction of triorganotin fluorides (Ph3SnF, Bu3SnF) with CaBr2 yields pure triorganotin bromides. 1 was found to act either as a fluoride-acceptor or, towards PF5, as a fluoride-donor. - Keywords: Trimethylfluorostannane; Triorganohalo-Stannanes; Phosphorus-Fluorine Compounds; NMR Spectra

Low temperature fluorination with elemental fluorine of elemental phosphorus, sulphur, silicon, amorphous carbon and phosphorus trichloride, phosphorus pentoxide, triphenylphosphine, hexafluorodisilane, hexachlorodisilane, hexabromodisilane, tetrasulphur tetranitride, sulphur dioxide, thionyl chloride and sulphuryl chloride has been carried out in freon-11 medium.The corresponding fluoro compounds have been isolated in near quanititative yields, purified by low temperature fractional condensation and characterised by IR spectroscopy and elemental analysis.

The preparations of the salts PH3F+SbF6- and PHF3+Sb2F11- are reported.All fluorophosphonium cations PH4-nFn+ are characterized by multinuclear (1H, 19F, 31P) NMR spectroscopy.For n > 1 these salts are easily accessible by fluoride abstraction from fluorohydridophosphates(V).PH3F+SbF6-, however, is obtained in the reaction of PH3F2 with SbF5. - keywords: Fluorophosphonium Salts, Formation, NMR Spectra

Argon/F2 and argon/PH3 samples codeposited at 16 K yielded reaction product infrared absorptions identified as PH3F2, PHF2, and the new molecule PH2F. In contrast the analogous NH3 and F2 system gave only the NH3- -F2 complex, which required photolysis to produce the NH2F- -HF complex. The phosphine-fluorine reaction apparently proceeds through a pentavalent activated complex. This activated complex either is relaxed by the matrix to give PH3F2 or dissociates to the PHF2 or PH2F products, which are trapped in the matrix.

-

Antimony pentafluoride and SbF3.SbF5 are reduced by an excess of phosphorus trifluoride, in liquid arsenic trifluoride to form (SbF3)3SbF5 together with possibly small amounts of antimony trifluoride.Antimony pentafluoride is similarly reduced by an excess of elemental iodine to (SbF3)3SbF5 but with larger amounts of antimony trifluoride.A single crystal X-ray diffraction study of (SbF3)SbF5 shows that it is monoclinic, space group P21/m, with cell dimensions a=10.895(3), b=10.941(3), c=4.772(1) Angstroem, β=96.66(3) deg, and Z=2.The structure was refined to a final R of 0.039 for 1694 reflections.The structure consists of discrete SbF6- anions and parallel strands of (Sb3F8+) which lie along the b axis.The polymeric strand can be considered to be composed of SbF3 and Sb2F5+ units joined by antimony-fluorine bridges .The vibrational spectrum of (SbF3)3SbF5 is reported.

A solution-calorimetric determination of the enthalpies of reaction of the α and β modifications of UF5 with Ce(SO4)2 + H2SO4 is described.Auxiliary measurements were made of the enthalpies of reaction of UO2, γ-UO3, and HF(aq).From these results are calculated the standard enthalpies of formation ΔH0f(298.15 K) of β-UF5, -(2083.0 +/- 6.3) kJ/mol and of α-UF5, -(2075.5 +/- 6.7) kJ/mol.The enthalpy of the (β-to-α) transition is (7.5 +/- 2.1) kJ/mol at 298.15 K.Suggested ΔH0f values are also given for U4F17 and U2F9.

-

Oxygen reacts with tris(trifluoromethyl)phosphine by a chain reaction involving the trifluoromethyl radical and its autoxidation. With thermal quenching, tris(trifluoromethyl) phosphate and bis(trifluoromethyl)fluorophosphine oxide are formed. Under conditions of spontaneous ignition the latter compound delivers CF2, a powerful reducing agent.

The interactions of tetrafluoroethylidene with three fluorine-containing phosphines have been investigated. The source of the carbene is the pyrolytic decomposition of C2F5SiF3 at 200°C. The reaction of CF3CF with PF3 generates CF2=CFPF4 and PF5; reaction with (CF3)3P leads to (CF3)2PCF(CF3)2; and reaction with (CF3)2PCF(CF3)2 produces the fluorocarbon (CF3)2CFCF(CF3)2. The possibility that the vinylphosphorane product of the PF3 reaction results from fluorine-transfer rearrangement of C2F5PF2 as an intermediate product was discredited by a demonstration that C2F5PF2 is thermally stable under the reaction conditions. Other mechanistic pathways are discussed.

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.

-