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چکیده
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Polychlorinated biphenyls (PCBs) congeners are anthropogenic organic compounds and well known today as ubiquitous environmental contaminants formulated as biphenyl rings with various numbers of chlorine atoms substituted onto its carbon positions. They are toxic, lipophilic and tend to be bioaccumulated [1,2]. The generalized interaction properties function (GIPF) methodology developed by Politzer and coworkers, which calculated molecular surface electrostatic potential (MSESP) on a density envelope surface [3,4]. In the present study, geometrical optimization and electrostatic potential calculations have been performed for 209 PCBs at the HF/6-31G* level of theory in Gaussian98 software. A number of statistically-based parameters have been obtained. Linear relationships between gas-chromatographic relative retention time (RRT), n-octanol/water partition coefficient, melting point, total surface area, Henry’s law constant, aqueous solubility and aqueous activity coefficients of PCBs and the structural descriptors have been established by multiple regression method. Good predictive capabilities have also been demonstrated. Based on these equations, the predicted values have been presented for those PCBs congeners whose experimentally determined physicochemical properties are unavailable and further compared with the results from similar researches published recently [5].
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