The thermal stabilities of RCN-XeFAsF] salts have been examined. These cations have been characterized in HF and/or BrF by Xe, F, N, N, C and H NMR spectroscopy and in the solid state by low-temperature Raman spectroscopy. The electron more » pairs of nitriles and perfluoropyridines have been shown to interact with the Lewis acid XeF resulting in the cations RCN-XeF (R = H, CH, CHF, CHCl, CH, CHFCH, n-CH, CHFCHCH, CHCHFCHCHFCHCHCHCFCH, n-CH, CHCHFCHCH, (CH)CH, (CH)C, FCHC (CH)H, ClCHC(CH)H and CF) and RCFN-XeF (R = F, 2-CF, 3-CF, 4-CF). Hydrogen cyanide, alkyl nitriles, perfluorophenyl nitrile and perfluoropyridine derivatives were investigated as potential ligands for xenon (II).
The key synthetic approach involves the interaction of the Lewis acid XeF with an organic nitrogen Lewis base, where the organic nitrogen base must be resistant to oxidation by the XeF cation. This work represents an extension of noble-gas chemistry and the synthesis of novel xenon-nitrogen bonded compounds. This Thesis describes the synthesis and spectroscopic characterization of noble-gas compounds containing Xe-N bonds in solution by multinuclear magnetic resonance (multi-NMR) spectroscopy and in the solid state by low-temperature Raman spectroscopy. For the range of composition in which C/sub x/F/sub 1-delta/(HF)/sub delta/ is an electrical conductor (x greater than or equal to 2.3), the fluorination was found to be electrochemically reversible. In these compounds, fluorine forms weak, semi-ionic bonds to the carbon atoms, which are disposed in virtually undistorted, planar sheets. = 12), which were studied by XPS, NMR, vibrational spectroscopy, and crystallographic methods. Fluorination of graphite in the presence of HF produced these salts and the first-stage hydrofluorides C/sub x/F/sub 1-delta/(HF)/sub delta/ (5 > x > 2, x/delta approx. The new graphite bifluorides, C/sub 12//sup +/HF/sub 2//sup -/ and C/sub 18//sup +/HF/sub 2//sup -/, were prepared their crystal structures establish that they are correctly formulated as graphite salts. The electron affinities of the more » third row transition metal hexafluorides were likewise re-evaluated. Lattice energy calculations and vapor pressure/temperature measurements established the following gas phase fluoride ion affinities: GeF/sub 4/, 100(6) BF/sub 3/, 92(6) AsF/sub 5/, 115(7) XeF/sub 5//sup +/, 202(7) ClF/sub 2//sup +/, 223(7) SF/sub 3//sup +/, 211(7) IF/sub 6//sup +/, 211(7) kcal mole/sup -1/.
The pentafluorogermanate ion was found to exist in one monomeric and at least three polymeric modifications in its salts. The pentafluorogermanate salts of a variety of cations (ClO/sub 2//sup +/, NO/sup +/, SF/sub 3//sup +/, NO/sub 2//sup +/, and XeF/sub 5//sup +/) were synthesized and characterized by x-ray crystallographic and vibrational methods. These species have been assigned tentative = , Several new species or phases are observed in the Raman spectra. This mixture near 1.3:1 forms a kinetically stable glass at room temperature and is molten at 50/sup 0/C. The binary phase diagram XeF/sub 2/:Xe/sup +//sub 5/AsF/sup -//sub 6/ was investigated by melting point determination and Raman spectroscopy. In the BrF/sub 3/ case, Br/sub 2/ is evolved and only Br(III) is present in the graphite. X-ray absorption studies were begun to determine the species present within the graphite when BrF/sub 3/ or GeF/sub 4/ + F/sub 2/ are added. Magnetic susceptibility of C/sup +//sub 8/OsF/sup -//sub 6/ confirms the high degree of oxidation in this compound. The C/sub x/AsF/sub 6/ and numerous standard arsenic-flourine compounds were studied by x-ray absorption. The compound C/sub x/AsF/sub 5/ was prepared and characterized by x-ray diffraction and x-ray absorption, which show the presence of As(III) and As(V), and the As-F bond distances are consistent with AsF/sub 3/ and AsF/sup -//sub 6/, C/sup +//sub 8/AsF/sup -//sub 6/ and C/sup +//sub 8/OsF/sup -//sub 6/ were synthesized.