0000000001284785
AUTHOR
Raman Chirakal
NMR Spectroscopic Evidence for the Intermediacy of XeF3− in XeF2/F− Exchange, Attempted Syntheses and Thermochemistry of XeF3− Salts, and Theoretical Studies of the XeF3− Anion
The existence of the trifluoroxenate(II) anion, XeF(3)(-), had been postulated in a prior NMR study of the exchange between fluoride ion and XeF(2) in CH(3)CN solution. The enthalpy of activation for this exchange, ΔH(⧧), has now been determined by use of single selective inversion (19)F NMR spectroscopy to be 74.1 ± 5.0 kJ mol(-1) (0.18 M) and 56.9 ± 6.7 kJ mol(-1) (0.36 M) for equimolar amounts of [N(CH(3))(4)][F] and XeF(2) in CH(3)CN solvent. Although the XeF(3)(-) anion has been observed in the gas phase, attempts to prepare the Cs(+) and N(CH(3))(4)(+) salts of XeF(3)(-) have been unsuccessful, and are attributed to the low fluoride ion affinity of XeF(2) and fluoride ion solvation in…
NMR Spectroscopic Evidence for the Intermediacy of XeF3– in XeF2/F– Exchange, Attempted Syntheses and Thermochemistry of XeF3– Salts, and Theoretical Studies of the XeF3– Anion
The existence of the trifluoroxenate(II) anion, XeF3−, had been postulated in a prior NMR study of the exchange between fluoride ion and XeF2 in CH3CN solution. The enthalpy of activation for this exchange, ΔH⧧, has now been determined by use of single selective inversion 19F NMR spectroscopy to be 74.1 ± 5.0 kJ mol−1 (0.18 M) and 56.9 ± 6.7 kJ mol−1 (0.36 M) for equimolar amounts of [N(CH3)4][F] and XeF2 in CH3CN solvent. Although the XeF3− anion has been observed in the gas phase, attempts to prepare the Cs+ and N(CH3)4+ salts of XeF3− have been unsuccessful, and are attributed to the low fluoride ion affinity of XeF2 and fluoride ion solvation in CH3CN solution. The XeF3− anion would rep…