title: Vibrational vs. translational energy in promoting a prototype metal-hydrocarbon insertion reaction.
abstract: The reaction Y + CH(4) --> HYCH(3) --> YCH(2) + H(2) is initiated by C-H insertion involving a 20 +/- 3 kcal/mol potential energy barrier. The reaction is studied in crossed molecular beams under two different conditions with nearly the same total energy. One experiment is carried out at a collision energy of 15.1 kcal/mol with one quantum of CH(4) antisymmetric (nu(3)) stretching vibrational excitation (8.63 kcal/mol), the other at a collision energy of 23.8 kcal/mol. The reaction cross-section for C-H stretch excited methane (sigma(s)) is found to be at least a factor of 2.2 times larger than for ground-state methane (sigma(g)) at the same total energy.
authors.affiliation: Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, NY 14853-1301, USA.
authors.forename: David L
authors.initials: DL
authors.lastname: Proctor
authors.forename: H Floyd
authors.initials: HF
authors.lastname: Davis