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New experimental evidence to support roaming in the reaction Cl?+?isobutene (i-C₄H₈).

ABSTRACT: The reaction Cl?+?isobutene (i-C₄H₈) was reported by Suits et al. to proceed via, in addition to abstraction, an addition-elimination path following a roaming excursion of Cl; a near-zero translational energy release and an isotropic angular distribution observed at a small collision energy characterized this mechanism. We employed a new experimental method to further characterize this roaming mechanism through observation of the internal distribution of HCl (v, J) and their temporal behavior upon irradiation of a mixture of Cl₂C₂O₂ and i-C₄H₈ in He or Ar buffer gas. With 1-3?Torr buffer gas added to approach the condition of small collision energy, the intensities of emission of HCl (v?=?1, 2) and the HCl production rates increased significantly; Ar shows a more significant effect than He because Ar quenches Cl more efficiently to reduce the collisional energy and facilitate the roaming path. According to kinetic modeling, the rate of addition-elimination (roaming) increased from k_E???2?×?10⁵?s^-1 when little buffer gas was present to ~1.9?×?10⁶?s^-1 when 2-3?Torr of Ar was added, and the branching ratio for formation of [HCl (v?=?2)]/[HCl (v?=?1)] increased from 0.02?±?0.01 for abstraction to 0.06?±?0.01 for roaming.

SUBMITTER: Chen LW

PROVIDER: S-EPMC5228202 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature

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New experimental evidence to support roaming in the reaction Cl + isobutene (i-C4H8).

Chen Li-Wei LW Hung Ching-Ming CM Matsui Hiroyuki H Lee Yuan-Pern YP

Scientific reports 20170112

The reaction Cl + isobutene (i-C4H8) was reported by Suits et al. to proceed via, in addition to abstraction, an addition-elimination path following a roaming excursion of Cl; a near-zero translational energy release and an isotropic angular distribution observed at a small collision energy characterized this mechanism. We employed a new experimental method to further characterize this roaming mechanism through observation of the internal distribution of HCl (v, J) and thei ...[more]

PMID: 28079173

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New experimental evidence to support roaming in the reaction Cl?+?isobutene (i-C₄H₈).

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New experimental evidence to support roaming in the reaction Cl + isobutene (i-C<sub>4</sub>H<sub>8</sub>).

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New experimental evidence to support roaming in the reaction Cl?+?isobutene (i-C4H8).

Publications

New experimental evidence to support roaming in the reaction Cl + isobutene (i-C<sub>4</sub>H<sub>8</sub>).

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

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New experimental evidence to support roaming in the reaction Cl?+?isobutene (i-C₄H₈).