Quantitative structure-property relationships for direct photolysis of polybrominated diphenyl ethers

Ecotoxicol Environ Saf. 2007 Mar;66(3):348-52. doi: 10.1016/j.ecoenv.2006.01.003. Epub 2006 Feb 20.

Abstract

Using semiempirical quantum chemical descriptors, by partial least squares (PLS) regression, quantitative structure-property relationships (QSPRs) were established for direct photolysis quantum yields (Phi) and rate constants (k) of polybrominated diphenyl ether congeners dissolved in water/methanol and methanol solutions, respectively, and irradiated by artificial ultraviolet A light. Q(cum)(2), a parameter indicating robustness and predictive abilities of PLS models, for the significant QSPR models is larger than 0.702. The gap of frontier molecular orbital energies (E(LUMO)-E(HOMO)) and the most positive Mulliken atomic charges on a hydrogen atom (q(H+)) are two main molecular structural factors governing the logPhi values. logPhi increases with increasing E(LUMO)-E(HOMO) and q(H+) values. logk is mainly related to bromination degree and pattern which can be characterized by molecular weight (Mw), average molecular polarizability (alpha), and average Mulliken atomic charges on bromine atoms (q(Br)). logk increases with bromination degree (Mw, alpha) and q(Br).

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Least-Squares Analysis
  • Methanol / chemistry
  • Phenyl Ethers / radiation effects*
  • Photolysis
  • Polybrominated Biphenyls / radiation effects*
  • Quantitative Structure-Activity Relationship*
  • Solvents / chemistry
  • Ultraviolet Rays*
  • Water / chemistry

Substances

  • Phenyl Ethers
  • Polybrominated Biphenyls
  • Solvents
  • Water
  • Methanol