In this project in the Physical Chemistry Program of the Chemistry Division, Peter Armentrout of the University of Utah will use flowing afterglow ion production and guided ion beam mass spectrometry in a systematic determination of gas phase reactivity and thermochemistry, especially of transition metal atomic and organometallic ions. Employing the technique of electronic state chromatography, Armentrout will also state select transition metal ions and study their dynamic behavior. Detailed kinetic and thermodynamic data will be obtained at both thermal and hyperthermal energies. Reactions of ions with a wide range of neutral reagents will be examined. %%% By studying reactions involving electrically charged molecules containing transition metal atoms, Armentrout can determine many properties of the corresponding neutral species, such as the stability of different molecules or the strength of bonds between these atoms and attached units called ligands. Such information is useful for understanding many processes, such as catalysis, which involve transition metals. The results of other phases of this work also impacts atmospheric chemistry and surface chemistry.