Mass spectrometric study of simple main group molecules and ions important in atmospheric processes

Recent mass spectrometric studies of simple inorganic species (both charged and neutral) of main-group elements are reviewed, focusing attention on radicals and ions of interest to the chemistry of the atmosphere and its pollution. The examples illustrated concern the detection of HO3, hydrogen trioxide, the O2/O3 isotope exchange and its charged intermediate O5 1, the reactions promoted by ionization of ozone/halocarbon mixtures in atmospheric gases, the ion chemistry of NOx oxides, and that of elemental chlorine and chlorine fluoride. Among the results of specific interest to gas-phase ion chemistry, the examples illustrated concern the intracluster ligand-switching reactions in ternary NO1 complexes, the NO2 1 reactivity towards ethylene and acetylene, the gas-phase basicity of Cl2, the formation and characterization of Cl2X1 ions (X 5 Cl, F) and of [H3C-Cl-Cl]1, a new isomer of protonated dichloromethane.