title: Partial control of an ion-molecule reaction by selection of the internal motion of the polyatomic reagent ion.
abstract: The ion-molecule reaction NH(3)(+) + ND(3) has been studied at various collision energies (1 to 5 electron volts in the center of mass) with preparation of the NH(3)(+) reagent in two nearly isoenergetic vibrational states. One state corresponds to pure out-of-plane bending of the planar NH(3)(+) ion (0.60 electron volts), whereas the other state is a combination of in-plane and out-of-plane motion (0.63 electron volts). The product branching ratios differ markedly for these two vibrational-state preparations. The differences in reactivity suggest that the in-plane totally symmetric stretching mode is essentially inactive in controlling the branching ratio of this reaction.
authors.forename: R D
authors.initials: RD
authors.lastname: Guettler
authors.forename: G C
authors.initials: GC
authors.lastname: Jones
authors.forename: L A
authors.initials: LA
authors.lastname: Posey
authors.forename: R N
authors.initials: RN
authors.lastname: Zare