title: Molecular beam studies of the F atom reaction with propyne: site specific reactivity.
abstract: The dynamics of the F atom reaction with propyne (CH(3)CCH) has been investigated using a universal crossed molecular beam apparatus. Two reaction channels have been clearly observed: H+C(3)H(3)F and HF+C(3)H(3). The substitution of F for H occurs mainly via a complex formation mechanism, producing reaction products with some contribution from a direct reaction mechanism. The HF product, however, appears to be dominantly forward scattered relative to the F atom beam direction, suggesting that the HF formation occurs via a direct abstraction mechanism. Branching ratios for the two observed reaction channels are also determined. The H formation channel is found to be the major reaction pathway, while the HF formation channel is also significant. From the measurements of DF versus HF products from the F atom reaction with deuterated propyne, the H atom picked up by the F atom in the reaction with normal propyne seems to come mostly from the CH(3) group. In addition, the H atom produced in the H atom formation channel appears to be mostly from the CH(3) group with some contribution from the CCH group.
authors.affiliation: Department of Chemistry, University of California at Santa Barbara, Santa Barbara, CA 93106, USA.
authors.forename: Qin
authors.initials: Q
authors.lastname: Ran
authors.forename: Chung Hsin
authors.initials: CH
authors.lastname: Yang
authors.forename: Yuan T
authors.initials: YT
authors.lastname: Lee
authors.forename: I-Chung
authors.initials: IC
authors.lastname: Lu
authors.forename: Guanlin
authors.initials: G
authors.lastname: Shen
authors.forename: Ling
authors.initials: L
authors.lastname: Wang
authors.forename: Xueming
authors.initials: X
authors.lastname: Yang