Dynamics of the reactions of C/sup +/ with C/sub 2/H/sub 6/

Journal Article · Sun Jan 15 04:00:00 EST 1989 · J. Chem. Phys.; (United States)

OSTI ID:6593132

Curtis, R A; Farrar, J M

We present a crossed beam study of the major reactive channels of C/sup +/+C/sub 2/H/sub 6/ in the collision energy range between 0.8 and 1.6 eV. We find that C/sub 2/H/sup +//sub 5/ formation proceeds as a direct hydride abstraction reaction with the accompanying CH product scattered in the forward hemisphere. The product recoil energy distribution shows a distinct Gaussian shape that we correlate with the nature of the potential energy surface for transfer of the light hydride ion between two heavy species. C/sub 2/H/sup +//sub 3/ formation occurs through two pathways: the first and most important route is direct interaction of C/sup +/ with C/sub 2/H/sub 6/ to form a new C--C bond with the ejection of CH/sub 3/ in a collinear interaction that leads to backward scattering of the ionic product. A second, and much less probable pathway involves formation of this product through a transient collision complex living a significant fraction of a rotational period. The condensation product C/sub 3/H/sup +//sub 3/ is by far the most abundant C/sub 3/ product observed in this collision energy range. The sideways-peaked angular distribution for its formation is consistent with a mechanism where the initially formed C/sub 3/H/sup +//sub 6/ complex decays in a step in which a molecule of H/sub 2/ is ejected in a direction perpendicular to the plane of rotation defined by the three carbon atoms. The kinetic energy distribution for this channel is significantly broader than the predictions of statistical phase space theory and underscores the importance of potential energy exit channel barriers in determining product recoil in such elimination processes. We discuss these results in the context of a schematic potential energy surface incorporating thermochemical data and results of ab initio calculations.

• Research Organization: Department of Chemistry, University of Rochester, Rochester, New York 14627
• OSTI ID: 6593132
• Journal Information: J. Chem. Phys.; (United States), Journal Name: J. Chem. Phys.; (United States) Vol. 90:2; ISSN JCPSA
• Country of Publication: United States
• Language: English

Related Subjects

640304* -- Atomic
Molecular & Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
ALKANES
ATOMIC IONS
BEAMS
CARBON IONS
CHARGED PARTICLES
CHEMICAL REACTIONS
COLLISIONS
DISTRIBUTION
ENERGY
ENERGY RANGE
ETHANE
EV RANGE
EV RANGE 01-10
HYDROCARBONS
ION BEAMS
ION COLLISIONS
ION-MOLECULE COLLISIONS
IONS
KINETIC ENERGY
MOLECULAR BEAMS
MOLECULE COLLISIONS
ORGANIC COMPOUNDS