State-Selected Reactivity of Carbon Dioxide Cations (CO2+) With Methane

Abstract

The reactivity of with CD 4 has been experimentally investigated for its relevance in the chemistry of plasmas used for the conversion of CO 2 in carbon-neutral fuels. Non-equilibrium plasmas are currently explored for their capability to activate very stable molecules (such as methane and carbon dioxide) and initiate a series of reactions involving highly reactive species (e.g., radicals and ions) eventually leading to the desired products. Energy, in the form of kinetic or internal excitation of reagents, influences chemical reactions. However, putting the same amount of energy in a different form may affect the reactivity differently. In this paper, we investigate the reaction of with methane by changing either the kinetic energy of or its vibrational excitation. The experiments were performed by a guided ion beam apparatus coupled to synchrotron radiation in the VUV energy range to produce vibrationally excited ions. We find that the reactivity depends on the reagent collision energy, but not so much on the vibrational excitation of . Concerning the product branching ratios ( / /DOCO + ) there is substantial disagreement among the values reported in the literature. We find that the dominant channel is the production of , followed by DOCO + and , as a minor endothermic channel.

Study of the Reactivity of CH3COOH+• and COOH+ Ions with CH3NH2: Evidence of the Formation of New Peptide-like C(O)–N Bonds

“…It is worth mentioning that the cross section related to the m / z 31 ion, associated with the charge transfer, shows a significant decrease with collision energy (with a slope close to the E –1/2 trend, drawn in Figure as a guide). This is surprising, as the usual behavior of charge transfer, due to its long-range interaction, is relatively insensitive to the collision energy as has been previously observed in our apparatus. − To reconcile these observations, our hypothesis is that the m / z 31 ion is a poorly stable product of charge transfer, which dissociates to form the m / z 30 ion. Indeed, the dissociative charge transfer of CH 3 NH 2 +• is known to occur for an internal energy of 1.5 eV .…”

Formation of H3+ in Collisions of H2+ with H2 Studied in a Guided Ion Beam Instrument

“…After a remarkable expansion in the eighties and nineties, there are only a few laboratories left today, using successfully this technique. Quite productive is still the GIB instrument CERISES, the University of Utah GIB instrument and the Università di Trento GIB instrument . Also the group of Cheuk Ng still operates a special GIB instrument using pulsed field photoionization for preparing ions in selected states .…”