Thermochemistry, Reactivity, and Dynamics of Metals Engaged in Chemiionization
Technical Report,15 Feb 2016,14 Aug 2019
University of Utah Salt Lake City United States
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The exothermicity of the chemi-ionization reaction M O MO e has been re evaluated for M Sm, Gd, and Nd. Guided ion beam tandem mass spectrometry GIBMS has been used to determine the bond dissociation energies BDEs of MO for all three metals, as determined by the observed reactivity of M and MO with several species. Combined with the established M ionization energies, these BDEs allow re-evaluation of the exothermicities of the chemi-ionization reactions. Implications of these results for interpretation of chemical release experiments in the thermosphere were evaluated. In addition, GIBMS work has also examined reactions of Sm with CO2 and OCS to form SmO and determined that these reactions exhibit barriers to their formation, which has been shown by theory to result from the need to couple the ground state surfaces of Sm 8F12,4f66s1 to an electronic surface evolving from the 132 4f55d6s excited state. Studies of the reactions of M with H2, HD, and D2 M Sm and Gd allowed BDEs of the metal hydride cations to be measured. In addition, reactions of Sm and SmS with sulfur donors allowed the SmS BDE to be determined and compared to advanced computational results. Potential energy surfaces for Gd,2O and Gd,C,2O systems were been evaluated experimentally. The BDE of Au2 has been measured and its reactivity with methane previously reported to show catalytic formation of ethene has been studied shown not to exhibit the aforementioned catalytic behavior. Oxidation of iron carbonyl cations has also been examined.
- Physical Chemistry