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Optimized calculation of dibenzofuran (DF) and 135 polychlorinated diben- zofurans (PCDFs ) was carried out at the B3LYP/6-31G* level in GAUSSIAN 98 program. Based on the theoretical linear solvation energy relationship (TLSER) model, the obtained structural parameters were taken as theoretical descriptors to establish the novel quantitative structure- property relationship (QSPR) model for predicting n-octanol/water partition coefficients (lgKow) of PCDFs. The new model of lgKow achieved in this work contains three variables: energy of the highest occupied molecular orbital (EHOMO), the most negative atomic partial charge (q-) and average molecular polarizability (α), of which R2 = 0.9011 and SD = 0.17 with larger t values. In addition, the variation inflation factors (VIF) of variables in the present model are all less than 5.5, suggesting high accuracy of the lgKow model. And the results of cross-validation test (q2 = 0.8688) and method validation also show this model exhibits optimum stability and better predictive power than semi-empirical method. At the same time, it is found that the aqueous solubility (-lgSw) has high relative correlation with constant volume molar heat capacity (CV0), of which R2 = 0.9777 and SD = 0.22. Moreover, lgKow and -lgSw values of all PCDF congeners were predicted respectively.
Optimized calculation of dibenzofuran (DF) and 135 polychlorinated dibenzofurans (PCDFs) was carried out at the B3LYP / 6-31G * level in GAUSSIAN 98 program. Based on the theoretical linear solvation energy relationship (TLSER) model, the obtained structural parameters were taken as theoretical descriptors to establish the novel quantitative structure-property relationship (QSPR) model for predicting n-octanol / water partition coefficients (lgKow) of PCDFs. The new model of lgKow achieved in this work contains three variables: energy of the highest The most negative atomic partial charge (q-) and the average molecular polarizability (α), of which R2 = 0.9011 and SD = 0.17 with larger t values. In addition, the variation inflation factors (VIF) of And the results of cross-validation test (q2 = 0.8688) and method validation also show this model exhibits opti mum stability and better predictive power than semi-empirical method. At the same time, it is found that the aqueous solubility (-lgSw) has high relative correlation with constant volume molar heat capacity (CV0) of which R2 = 0.9777 and SD = 0.22. Moreover, lgKow and -lgSw values of all PCDF congeners were predicted respectively.