Interdisciplinary Nanotoxicity Center, Department of Chemistry and Biochemistry, Jackson State University, 1400 Lynch Street, P.O. Box 17910, Jackson, Mississippi 39217, USA.
J Phys Chem A. 2011 Mar 24;115(11):2423-30. doi: 10.1021/jp112240d. Epub 2011 Mar 1.
This study presents new insight into the prediction of partitioning of organic compounds between a carbon surface (soot) and water, and it also sheds light on the sluggish desorption of interacting molecules from activated and nonactivated carbon surfaces. This paper provides details about the structure and interactions of benzene, polycyclic aromatic hydrocarbons, and aromatic nitrocompounds with a carbon surface modeled by coronene using a density functional theory approach along with the M05-2X functional. The adsorption was studied in vacuum and from water solution. The molecules studied are physisorbed on the carbon surface. While the intermolecular interactions of benzene and hydrocarbons are governed by dispersion forces, nitrocompounds are adsorbed also due to quite strong electrostatic interactions with all types of carbon surfaces. On the basis of these results, we conclude that the method of prediction presented in this study allows one to approach the experimental level of accuracy in predicting thermodynamic parameters of adsorption on a carbon surface from the gas phase. The empirical modification of the polarized continuum model leads also to a quantitative agreement with the experimental data for the Gibbs free energy values of the adsorption from water solution.
本研究为预测有机化合物在碳表面（ soot）和水中的分配提供了新的见解，也揭示了相互作用分子从活性炭和非活性炭表面缓慢解吸的原因。本文详细介绍了苯、多环芳烃和芳香族硝基化合物与通过密度泛函理论方法和 M05-2X 函数建模的 coronene 碳表面之间的结构和相互作用。吸附在真空和水溶液中进行了研究。所研究的分子在碳表面上发生物理吸附。虽然苯和碳氢化合物的分子间相互作用受色散力控制，但由于与各种类型的碳表面存在相当强的静电相互作用，硝基化合物也被吸附。基于这些结果，我们得出结论，本研究提出的预测方法可以在从气相预测碳表面吸附的热力学参数方面达到实验精度水平。极化连续体模型的经验修正也导致与从水溶液吸附的吉布斯自由能值的实验数据定量一致。
