title: Gas-phase tropospheric chemistry of 2,3,7,8-tetrafuorinated dibenzo-p-dioxin.
abstract: Growing attention has been devoted to understanding the formation and destruction of polyfluorinated dibenzo-p-dioxins (PFDDs). High-accuracy molecular orbital calculations have been performed to investigate the tropospheric oxidation reaction of 2,3,7,8-tetrafuorinated dibenzo-p-dioxin (TFDD) initiated by OH radical, NO3 radical and O3. The rate constant of TFDD reaction triggered by the OH radical, NO3 radical and O3 is about 2.30 × 10(-11)cm(3) molecule(-l) s(-l), 3.18 × 10(-13)cm(3) molecule(-l) s(-l), and 3.30 × 10(-19)cm(3) molecule(-l) s(-l), respectively. OH radical is the major gas phase tropospheric sink for TFDD. Once TFDD-OH intermediates are produced in the initial reactions, they can react with tropospheric O2 subsequently to generate peroxy radical isomers. The TFDD-OH-O2 can further react with tropospheric NO via isomerization or combination, resulting that the dioxin ring will be ruptured completely. This study can serve as a template for tropospheric degradation of the gaseous PFDDs, which is beneficial for assessing their tropospheric behaviors.
authors.affiliation: Environment Research Institute, Shandong University, Jinan 250100, PR China.
authors.forename: Chenxi
authors.initials: C
authors.lastname: Zhang
authors.forename: Xiaomin
authors.initials: X
authors.lastname: Sun
mesh_terms: D000393:Air Pollutants / Q000032:analysis* / Q000737:chemistry; D001272:Atmosphere / Q000737:chemistry*; D004147:Dioxins / Q000032:analysis* / Q000737:chemistry; D006878:Hydroxides / Q000737:chemistry; D007700:Kinetics; D015394:Molecular Structure; D009566:Nitrates / Q000737:chemistry; D010126:Ozone / Q000737:chemistry
chemical_list: C092566:2,3,7,8-tetrafluorodibenzodioxin; D000393:Air Pollutants; D004147:Dioxins; D006878:Hydroxides; D009566:Nitrates; D010126:Ozone; C031356:hydroxide ion
keywords: Gas-phase tropospheric chemistry; NO(3) radical; O(3); OH radical; TFDD