拜高杀虫剂与腐植酸模型化合物相互作用的理论研究

The oretical study of interactions between propoxur and the model humic acid

本文运用理论量子化学方法研究拜高杀虫剂与甲酸(最简单的腐植酸官能团的模型化合物)的相互作用。结果表明,拜高与甲酸二者以氢键形成复合体,其复合体主要分为两类:(1)分子间距离r=3.4?,分子间存在强静电作用,键能ΔE=67.2kJ/mol,从拜高转移至甲酸的电荷CT=0.0062e。(2)当拜高分子的酰胺与甲酸两个平面处于垂直位置时,分子间距离r=2.8?形成较弱的复合体,当从拜高转移至甲酸的电荷CT=0.0015e,键能和偶极距分别减少为39.1kJ/mol和7.5D。

The theoretical quantum-chemical CNDO/2 calculations were carried out to determine the interaction between propoxur (phenyl N·methylcarbamate) and the tormic acid (the simplest model for functional groups of humic substances).The formic acid formed the H-bond complexes with propoxur.These complexes can be classified into two main categories:First,the strong clectroatane interaction,at the distance r=3.40 ?,between carbamate group of the propoxur and the formic acid molecule (lie in a common plane) with the binding energy ΔE=67.2kJ/mol.The charge 0.0062e is transferred from propoxur towards formic acid.Second,the weaker complex where formic acid molecule is 2.8? above the aromatic ring in plane perpendicular the propoxur.The decrease in transferred charge to 0.0015e the binding energy to 39.1 kJ/mol anddipole moment to 7.5 D was observed.