Details zur Publikation

Kategorie Textpublikation
Referenztyp Zeitschriften
DOI 10.1016/j.chemosphere.2015.08.012
Titel (primär) Modeling and predicting pKa values of mono-hydroxylated polychlorinated biphenyls (HO-PCBs) and polybrominated diphenyl ethers (HO-PBDEs) by local molecular descriptors
Autor Yu, H.; Wondrousch, D.; Yuan, Q.; Lin, H.; Chen, J.; Hong, H.; Schüürmann, G.
Journal / Serie Chemosphere
Erscheinungsjahr 2015
Department OEC
Band/Volume 138
Seite von 829
Seite bis 836
Sprache englisch
Keywords Hydroxylated polychlorinated biphenyls; Hydroxylated polybrominated diphenyl ethers; Dissociation constant; pKa; HF/6-31G∗∗; Local molecular parameters
UFZ Querschnittsthemen RU3;
Abstract Hydroxylated polychlorinated biphenyls (HO-PCBs) and polybrominated diphenyl ethers (HO-PBDEs) are attracting considerable concerns because of their multiple endocrine-disrupting effects and wide existence in environment and organisms. The hydroxyl groups enable these chemicals to be ionizable, and dissociation constant, pKa, becomes an important parameter for investigating their environmental behavior and biological activities. In this study, a new pKa prediction model was developed using local molecular descriptors. The dataset contains 21 experimental pKa values of HO-PCBs and HO-PBDEs. The optimized geometries by ab initio HF/6-31G∗∗ algorithm were used to calculate the site-specific molecular readiness to accept or donate electron charges. The developed model obtained good statistical performance, which significantly outperformed commercial software ACD and SPARC. Mechanism analysis indicates that pKa values increase with the charge-limited donor energy EQocc on hydroxyl oxygen atom and decrease with the energy-limited acceptor charge QEvac on hydroxyl hydrogen atom. The regression model was also applied to calculate pKa values for all 837 mono-hydroxylated PCBs and PBDEs in each class, aiming to provide basic data for the ecological risk assessment of these chemicals.
dauerhafte UFZ-Verlinkung https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=16486
Yu, H., Wondrousch, D., Yuan, Q., Lin, H., Chen, J., Hong, H., Schüürmann, G. (2015):
Modeling and predicting pKa values of mono-hydroxylated polychlorinated biphenyls (HO-PCBs) and polybrominated diphenyl ethers (HO-PBDEs) by local molecular descriptors
Chemosphere 138 , 829 - 836