title: Reactions of Ions with Ionic Liquid Vapors by Selected-Ion Flow Tube Mass Spectrometry.
abstract: Room-temperature ionic liquids exert vanishingly small vapor pressures under ambient conditions. Under reduced pressure, certain ionic liquids have demonstrated volatility, and they are thought to vaporize as intact cation-anion ion pairs. However, ion pair vapors are difficult to detect because their concentration is extremely low under these conditions. In this Letter, we report the products of reacting ions such as NO(+), NH4(+), NO3(-), and O2(-) with vaporized aprotic ionic liquids in their intact ion pair form. Ion pair fragmentation to the cation or anion as well as ion exchange and ion addition processes are observed by selected-ion flow tube mass spectrometry. Free energies of the reactions involving 1-ethyl-3-methylimidazolium bis-trifluoromethylsulfonylimide determined by ab initio quantum mechanical calculations indicate that ion exchange or ion addition are energetically more favorable than charge-transfer processes, whereas charge-transfer processes can be important in reactions involving 1-butyl-3-methylimidazolium dicyanamide.
authors: Steven D
authors: SD
authors: Chambreau
authors: Jerry A
authors: JA
authors: Boatz
authors: Ghanshyam L
authors: GL
authors: Vaghjiani
authors: §Air Force Research Laboratory, AFRL/RVBXT Space Vehicles Directorate, Hanscom Air Force Base, Massachusetts 01731, United States.|⊥Department of Physics, University of Puerto Rico, Mayaguez, Puerto Rico 00681-9016.|#Institute for Scientific Research, Boston College, Chestnut Hill, Massachusetts 02467, United States.
authors: Jeffrey F
authors: JF
authors: Friedman
authors: §Air Force Research Laboratory, AFRL/RVBXT Space Vehicles Directorate, Hanscom Air Force Base, Massachusetts 01731, United States.|#Institute for Scientific Research, Boston College, Chestnut Hill, Massachusetts 02467, United States.|¶Department of Chemistry, St. Anselm College, 100 Saint Anselm Drive, Manchester, New Hampshire 03102, United States.
authors: Nicole
authors: N
authors: Eyet
authors: §Air Force Research Laboratory, AFRL/RVBXT Space Vehicles Directorate, Hanscom Air Force Base, Massachusetts 01731, United States.
authors: A A
authors: AA
authors: Viggiano
keywords: RTIL; SIFT; carbene; ion attachment; ion pair