Abstract
Gas phase ion chemistry using the selected ion flow tube (SIFT) technique is discussed with the focus on fundamental studies on ion structure, energetics, reactivity, and dynamics: Laser-induced fluorescence (LIF) kinetics/dynamics of N2+(v) ions (vibrationally state-selected ion-molecule reactions; energy transfer processes), mechanisms of prototypical organic ion reactions (SN2 nucleophilic substitution and kinetic isotope effects; hydrogen/deuterium exchange; isotope effects in termolecular association), and ion-molecule reactions with biological implications (SN2 reactions at a nitrogen center; ECO2 elimination reactions of alkyl hydroperoxides). Anion chemistry of small nitroalkanes is also presented. A powerful combination of SIFT and negative ion photoelectron spectroscopy is used to study thermochemistry and structure of energetic and exotic ions (alkyl peroxides; anionic derivatives of diazo and azole compounds, cyclooctatetraene, and cyclopentanone). Finally, some of the new directions in SIFT research are discussed, i.e., reactions of ions with polyatomic organic radicals, and chemical ionization mass spectrometry with new detection schemes.
