物理化学学报 >> 2014, Vol. 30 >> Issue (9): 1616-1624.doi: 10.3866/PKU.WHXB201406182

理论与计算化学 上一篇    下一篇

有机污染物在碳纳米管吸附的定量结构-性质关系

刘芬1,2, 邹建卫1, 胡桂香1, 蒋勇军1   

  1. 1. 浙江大学宁波理工学院生物与化学工程学院, 浙江宁波 315100;
    2. 浙江大学化学工程与生物工程学系, 杭州 310027
  • 收稿日期:2014-04-30 修回日期:2014-06-17 发布日期:2014-08-29
  • 通讯作者: 邹建卫 E-mail:jwzou@nit.zju.edu.cn
  • 基金资助:

    国家自然科学基金(21272211)和宁波市科技计划(2011A610021,2013D1003)资助项目

Quantitative Structure-Property Relationship Studies on the Adsorption of Aromatic Contaminants by Carbon Nanotubes

LIU Fen1,2, ZOU Jian-Wei1, HU Gui-Xiang1, JIANG Yong-Jun1   

  1. 1. College of Biological and Chemical Engineering, Ningbo Institute of Technology, Zhejiang University, Ningbo 315100, Zhejiang Province, P. R. China;
    2. Department of Chemical Engineering and Biological Engineering, Zhejiang University, Hangzhou 310027, P. R. China
  • Received:2014-04-30 Revised:2014-06-17 Published:2014-08-29
  • Contact: ZOU Jian-Wei E-mail:jwzou@nit.zju.edu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (21272211) and Program of Science and Technology of Ningbo, China (2011A610021, 2013D1003).

摘要:

对一系列共59个芳香性分子进行了HF/6-31G*水平上的结构优化,并在优化结构上进行了分子静电势及其导出参数的计算,应用多元线性回归方法建立了碳纳米管吸附有机污染物的平衡常数与分子结构间的定量关系. 结果表明,分子表面静电势参数(Vminσ+2 和ΣVind+)结合分子表面积(S)和最低空轨道能级(εLUMO)可以很好地用于构建碳纳米管吸附的定量结构-性质关系(QSPR)模型. 模型中引入的参数均具有明确的物理意义,其合理性可以从污染物与碳纳米管或水分子间相互作用的角度进行解释. 模型的稳定性和预测能力经“留一法”和Monte Carlo 交叉验证法进行了确证. 本文亦采用支持向量机(SVM)、最小二乘支持向量机(LSSVM)和高斯过程(GP)等三种方法建立了上述参数与碳纳米管吸附性质的非线性模型. SVM和LSSVM模型表现出强的拟合能力,但预测能力明显不如其他模型. GP模型无论是拟合能力还是预测能力都是最佳,但并没有明显地优于线性模型,说明对本文研究体系而言,其分子结构与性质间的关系主要以线性形式存在.

关键词: 碳纳米管, 有机污染物, 分子表面静电势, 定量结构-性质关系, 高斯过程

Abstract:

Ab initio calculations have been performed for a group of 59 aromatic compounds at the HF/6-31G* level of theory. Electrostatic potentials (ESPs) and the statistically based structural descriptors derived from ESPs on the molecular surface have been obtained. The linear relationships between the adsorption equilibrium constants of organic contaminants by carbon nanotubes and the theoretical descriptors have been established by multiple linear regression. It is shown that the quantities derived from electrostatic potentials, Vmin, σ+2 and ΣVind+ together with the molecular surface area (S) and the energy level of lowest occupied molecular orbital (εLUMO) can be used to express the quantitative structure-property relationship (QSPR) of this sample set. All of the descriptors introduced in the QSPR models have definite physical meanings and their reasonability can be explained in terms of intermolecular interactions between the aromatic pollutants and carbon nanotubes or water. The stabilities and predictive powers of the models have been validated by "leave-one-out" and Monte Carlo cross-validation methods. Three nonlinear modeling techniques, namely supported vector machine (SVM), least-square supported vector machine (LSSVM), as well as Gaussian process (GP), have also been used to construct the predictive models. Though the SVM and LSSVM models exhibit strong fitting abilities, their predictive powers are inferior to the other models tested. The GP model yields the best fit and predictive ability among all of the models. Its advantage over the linear model, however, is not as remarkable as expected, which means that the relationship between the molecular structure and the adsorption property for the present system is primarily linear.

Key words: Carbon nanotube, Organic contaminant, Electrostatic potentials on molecular surface, Quantitative structure-property relationship, Gaussian process

MSC2000: 

  • O641