作　　者： ; ; ; ;

机构地区： 华南理工大学环境科学与工程学院

出　　处： 《环境化学》 2005年第4期459-462,共4页

摘　　要： 应用量子化学从头算HF/6-311+G(d)和B3LYP/6-311+G(d)方法计算了16种PAHs的多种量子化学参数,选取六种参数为分子结构的描述符,采用最小二乘法对16种PAHs的光解半衰期进行逐步多元线性回归分析,得到两个PAHs光解半衰期的QSAR模型,模型具有较高的相关系数,可有效地用于预测PAHs的光解半衰期.结果表明,HF方法所得模型优于B3LYP方法所得的模型.所得模型与基于半经验PM3算法的QSAR模型相比较,HF从头算方法所建立的QSAR模型比半经验PM3算法的结果要好.在所考查的诸多参数中,分子最高占有轨道特征值EHOMO,对PAHs光解半衰期起着决定作用.最后,运用所得模型预测了3种PAHs的光解半衰期. Based on some quantum chemical descriptors computed at the HF/6-311+G(d)and B3LYP/6-311+ G(d) level with the ab initio method of quantum chemistry, by the use of least squares analysis of six descriptors, two quantitative structure-activity relationship (QSAR) models for photolysis half-lives of selected 13 polycyclic aromatic hydrocarbons (PAHs) were obtained through stepwise multivariate linear regression. The correlation coefficients of the obtained models are significant. The results showed the HF theory is better than B3LYP theory in developing a QSAR model for photolysis half-lives of PAHs. The comparison of the obtained models in this study with the QSAR model based on the descriptors computed from PM3 Hamiltonian showed that the HF model derived from ab initio method was better than the PM3 one. The eigenvalue of the highest occupied molecular orbital plays a decisive role on the photolysis half - lives of PAHs in all descriptors studied in this work. Photolysis half-lives of three other PAHs without reported values were predicted at the end of this study.

关 键 词： 量子化学研究 光解 多环芳烃 模型 多元线性回归分析 量子化学从头算 方法 算法 活性 量子化学参数 半衰期 最小二乘法 从头算方法 分子结构 相关系数 方法 模型预测 半经验 描述符 多参数 特征值

领　　域： [理学] [理学] [一般工业技术]