Oxidation of bromide ions by hydroxyl radicals: spectral characterization of the intermediate BrOHâ¢-.
J Phys Chem A
; 117(5): 877-87, 2013 Feb 07.
Article
in En
| MEDLINE
| ID: mdl-23298154
ABSTRACT
The reaction of (â¢)OH with Br(-) has been reinvestigated by picosecond pulse radiolysis combined with streak camera absorption detection and the obtained spectro-kinetics data have been globally analyzed using Bayesian data analysis. For the first time, the absorption spectrum of the intermediate species BrOH(â¢-) has been determined. This species absorbs in the same spectral domain as Br(2)(â¢-) the band maximum is roughly at the same wavelength (λ(max) = 352 nm instead of 354 nm) but the extinction coefficient is smaller (ε(max) = 7800 ± 400 dm(3) mol(-1) cm(-1) compared with 9600 ± 300 dm(3) mol(-1) cm(-1)) and the band is broader (88 nm versus 76 nm). Quantum chemical calculations have also been performed and corroborate the experimental results. In contrast to Br(2)(â¢-), the existence of several water-BrOH(â¢-) configurations leading to different transition energies may account for the broadening of the absorption spectrum in addition to the higher number of degrees of freedom.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Bromides
/
Hydroxyl Radical
Language:
En
Journal:
J Phys Chem A
Journal subject:
QUIMICA
Year:
2013
Document type:
Article
Affiliation country:
France
Publication country:
EEUU
/
ESTADOS UNIDOS
/
ESTADOS UNIDOS DA AMERICA
/
EUA
/
UNITED STATES
/
UNITED STATES OF AMERICA
/
US
/
USA