Trends in bond dissociation energies of brominated flame retardants from density functional theory

摘要: Bond dissociation enthalpies (BDEs) are computed using the Density Functional Theory (DFT) for a selected set of C–Br, C–O, and C–Br bonds susceptible to homolysis in thermal degradation four brominated flame retardants (BFRs): decabromo-diphenyl, decabromo-diphenylethane, 1,2-bis(2,4,6-tribromophenoxy)-ethane, 3,4,5,6-tetrabromo-1,2-diethyl-phtalate. Based on BDEs at M06/cc-pVTZ level, choice based previous benchmark, we find debromination as dominant decomposition pathway diphenyls phtalates, whereas scission form phenoxyls benzyl radicals is preferred aromatic BFRs containing ether alkyl bridges, respectively. Trends rationalized terms (de)localization spin density electronic structure resulting radicals.