A novel model to predict gas–phase hydroxyl radical oxidation kinetics of polychlorinated compounds
Abstract In this study, a novel model based on aromatic meta–substituent grouping was presented to predict the second–order rate constants ( k ) for OH oxidation of PCBs in gas–phase. Since the oxidation kinetics are dependent on the chlorination degree and position, we hypothesized that it may be more accurate for k value prediction if we group PCB congeners based on substitution positions ( i.e. , ortho ( o ), meta ( m ), and para ( p )). To test this hypothesis, we examined the correlation of polarizability ( α ), a quantum chemical based descriptor for k values, with an empirical Hammett constant ( σ + ) on each substitution position. Our result shows that α is highly linearly correlated to ∑ σ o,m,p + based on aromatic meta–substituents leading to the grouping based predictive model. With the new model, the calculated k values exhibited an excellent agreement with experimental measurements, and greater predictive power than the quantum chemical based quantitative structure activity relationship (QSAR) model. Further, the relationship of α and ∑ σ o,m,p + for PCDDs congeners, together with highest occupied molecular orbital (HOMO) distribution, were used to validate the aromatic meta–substituent grouping method. This newly developed model features a combination of good predictability of quantum chemical based QSAR model and simplicity of Hammett relationship, showing a great potential for fast and computational tractable prediction of k values for gas–phase OH oxidation of polychlorinated compounds. Highlights A novel aromatic meta–substituent grouping model for k of OH oxidation of PCBs. Polarizability is highly correlated to Hammett constant based on meta–substituents. This model features a combination of good predictability and simplicity. Graphical abstract [DISPLAY OMISSION]
- 원문이 없습니다.
- DOI : http://dx.doi.org/10.1016/j.chemosphere.2017.01.014
- Elsevier : 저널> 권호 > 논문
NDSL에서는 해당 원문을 복사서비스하고 있습니다. 위의 원문복사신청 또는 장바구니 담기를 통하여 원문복사서비스 이용이 가능합니다.
- 이 논문과 함께 출판된 논문 + 더보기