Structure and vibrational spectra of bromine reservoir species from the atmospheric oxidations of bromoethane and bromopropane

Abstract

Uncertainty in the ozone effects of bromoethane and bromopropane is associated with the lack of information regarding their respective brominated by-products for the atmospheric degradation chemistry. Ab initio molecular orbital methods at the density functional theory have been used to determine the fundamental IR vibrational modes of HC(O)H, CH3C(O)H, BrC(O)H, BrCH2C(O)H, BrCH2CH2C(O)H, CH3C(O)CH3, BrC(O)CH3, BrC(O)CH2CH3, and BrCH2C(O)CH3. A complete assignment for all the fundamental modes has been made for all the species under study. The vibrational infrared spectra of the brominated reservoir species is theoretically modelled and compared with experimental values where available. Rotational constants are calculated and compared with those in the literature.