1,1,1-三甲胺基甲酰亚胺分子结构的量化计算  

Calculation of the molecular structure of 1,1,1-trimethylamine-methanimide

作　　者：李正莉[1] 张有智[1] 王煊军[1] 樊瑞君[1] 

机构地区：[1]第二炮兵工程学院,陕西西安710025

出　　处：《北京化工大学学报（自然科学版）》2009年第2期27-32,共6页Journal of Beijing University of Chemical Technology(Natural Science Edition)

摘　　要：采用量子化学中的DFT/B3LYP和MP2方法研究了1,1,1-三甲胺基甲酰亚胺HC(O)N-N+(CH3)3的分子结构,在计算得到的平衡几何构型基础上进行了分子轨道(MO)和自然键轨道(NBO)计算。通过几何构型全优化,发现该分子存在Z型(顺式)和E型(反式)2种异构体,2种异构体中都存在一个对称平面,胺基酰亚胺官能团C(=O)N-N+位于这个对称平面上。分子的几何结构参数及MO和NBO分析都表明在这2种异构体中,N-的p轨道孤对电子都与羰基π键存在很强的共轭效应,Z型异构体中存在2个强度较弱的分子内氢键O…H—C。由分子总能量、离域π键的强度和H键可以表明Z型异构体比E型异构体更稳定。The molecular structure of 1, 1, 1-trimethylamine-methanimide, HC （=O） N^- N^＋ （CH3） 3, has been investigated by DFT/B3LYP and MP2 quantum mechanical methods. MO and NBO calculations have been carried out on the optimal equilibrium geometrical conformations. Through full geometrical optimization, two conformational isomers, namely the Z（cis）-isomer and the E（trans）-isomer, are found. A mirror plane is present in both isomers and the functional group C（=O）N-N＋ is situated in the plane. All of the calculations of geometrical structure parameters, MOs and NBOs show that the LPN- p orbital is conjugated with the O =C π bond. There are two intramolecular hydrogen bonds O… H-C in the Z-isomer. On the basis of comparisons of total molecular energy, and delocalized π bond and hydrogen bond strength, the Z-isomer is found to be more stable than the E-isomer.

关 键 词：量子化学 1 1 1-三甲胺基甲酰亚胺 分子结构 

分 类 号：O641[理学—物理化学] O561.1[理学—化学]