Title

Isomerization as a Key Path to Molecular Products in the Gas-Phase Decomposition of Halons

Document Type

Article

Language

eng

Format of Original

6 p.

Publication Date

2010

Publisher

American Chemical Society

Source Publication

Journal of Physical Chemistry Letters

Source ISSN

1948-7185

Abstract

The decomposition of halons remains controversial concerning the branching between radical and molecular products. The latter channel, where it has been found, is presumed to occur via a constrained symmetric multicenter transition state. Isomerization pathways in the gas-phase chemistry of halons have rarely been considered, despite the fact that the iso-halons, which feature a halogen−halogen bond, are widely recognized as important reactive intermediates in condensed phases. In this Letter, detailed calculations and modeling of the unimolecular decomposition of several important halons, including CF2Cl2, CF2Br2, and CHBr3, reveal that isomerization is a key pathway to molecular products. This path is important for both halons and their primary radicals as the barrier to isomerization in these compounds is typically isoenergetic with the threshold for bond fission.

Comments

Journal of Physical Chemistry Letters, Vol. 1, No. 20 (2010): 3090-3095. DOI.