Absolute state-selected and state-to-state total cross sections for the Ar sup + ( sup 2 P sub 3/2,1/2 )+CO sub 2 reactions

Journal Article · Wed Jul 01 04:00:00 EDT 1992 · Journal of Chemical Physics; (United States)

DOI:https://doi.org/10.1063/1.463616· OSTI ID:7034817

Flesch, G D; Ng, C Y ^[1]

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1. Ames Laboratory, U. S. Department of Energy, and Department of Chemistry, Iowa State University, Ames, Iowa 50011 (United States)

Absolute spin--orbit state-selected total cross sections for the reactions, Ar{sup +}({sup 2}{ital P}{sub 3/2,1/2})+CO{sub 2}{r arrow}CO{sup +}{sub 2}+Ar (reaction (1)), CO{sup +}+O+Ar (reaction (2)), O{sup +}+CO+Ar (reaction (3)), C{sup +}+2O+Ar (reaction (4)), ArC{sup +}+2O (reaction (5)), ArO{sup +}+CO (reaction (6)), and ArCO{sup +}+O (reaction (7)) have been measured in the center-of-mass collision energy ({ital E}{sub c.m.}) range of 0.26--131 eV. The ratio of the charge-transfer cross section due to Ar{sup +}({sup 2}{ital P}{sub 1/2}) to that associated with Ar{sup +}({sup 2}{ital P}{sub 3/2}) varies in the range of 0.5--0.8. The appearance energies observed for CO{sup +} ({ital E}{sub c.m.}=4.2{plus minus}0.5 eV), O{sup +} ({ital E}{sub c.m.}=3.7{plus minus}0.5 eV), and C{sup +} ({ital E}{sub c.m.}=12.6{plus minus}0.5 eV) are in agreement with the thermochemical thresholds for reactions (2), (3), and (4), respectively. The comparison of the absolute cross sections for CO{sup +}, O{sup +}, and C{sup +} from CO{sub 2} by photoionization and by dissociative charge transfer (reactions (2)--(4)) is made. The kinetic-energy analysis of product CO{sup +}{sub 2}, CO{sup +}, O{sup +}, C{sup +}, ArO{sup +}, and ArC{sup +} suggests that reactions (2)--(7) proceed via a charge-transfer predissociation mechanism. This experiment, together with the previous studies of Ar{sup +}({sup 2}{ital P}{sub 3/2,1/2})+N{sub 2}(O{sub 2},CO), supports the conclusion that product ions formed by dissociative photoionization are also produced by dissociative charge transfer.

• OSTI ID: 7034817
• Journal Information: Journal of Chemical Physics; (United States), Journal Name: Journal of Chemical Physics; (United States) Vol. 97:1; ISSN JCPSA; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201 -- Chemical & Physicochemical Properties
664300* -- Atomic & Molecular Physics-- Collision Phenomena-- (1992-)
74 ATOMIC AND MOLECULAR PHYSICS
ARGON IONS
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON OXIDES
CATIONS
CHALCOGENIDES
CHARGE EXCHANGE
CHARGED PARTICLES
CHEMICAL REACTIONS
COLLISIONS
COUPLING
CROSS SECTIONS
DISSOCIATION
ENERGY
ENERGY LEVELS
INTERMEDIATE COUPLING
ION COLLISIONS
ION-MOLECULE COLLISIONS
IONIZATION
IONS
KINETIC ENERGY
L-S COUPLING
MOLECULE COLLISIONS
OXIDES
OXYGEN COMPOUNDS
P STATES
PHOTOIONIZATION
TOTAL CROSS SECTIONS