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化学学报
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化学学报 ›› 2011, Vol. 69 ›› Issue (13): 1509-1516. 上一篇    下一篇

研究论文

C6FmH6－m (m＝1～6)结构及芳香性的理论研究

张敏1, 刘子忠*,1, 田维全2, 刘东升3, 葛湘巍3   

  1. (1内蒙古师范大学化学与环境科学学院功能材料物理与化学自治区重点实验室 呼和浩特 010022)
    (2哈尔滨工业大学理论与模拟化学研究所基础与交叉科学研究院城市水资源与水环境国家重点实验室
    哈尔滨 150080)
    (3内蒙古师范大学计算机工程与信息学院 呼和浩特 010022)
  • 投稿日期:2010-12-10 修回日期:2011-02-25 发布日期:2011-03-28
  • 通讯作者: 刘子忠 E-mail:zizhliu@yahoo.com.cn
  • 基金资助:

    国家自然科学基金;内蒙古自然科学基金;内蒙古师范大学研究生科研创新基金;城市水资源与水环境国家重点实验室(哈尔滨工业大学)自主课题

Theoretical Predictions on Structures and Aromaticities for C6FmH6－m (m＝1～6)

Zhang Min1; Liu Zizhong*,1; Tian Weiquan2; Liu Dongsheng3; Ge Xiangwei3   

  1. (1 College of Chemistry and Environmental Science, Inner Mongolia Key Laboratory for Physics and Chemistry of Functional Materials, Inner Mongolia Normal University, Hohhot 010022)
    (2 State Key Lab of Urban Water Resource and Environment(HIT), Institute of Theoretical and Simulational Chemistry, Academy of Fundamental and Interdisciplinary Sciences, Harbin Institute of Technology, Harbin 150080)
    (3 Computer & Information Engineering College, Inner Mongolia Normal University, Hohhot 010022)
  • Received:2010-12-10 Revised:2011-02-25 Published:2011-03-28
  • Contact: zizhong liu E-mail:zizhliu@yahoo.com.cn

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运用密度泛函理论方法B3LYP, 选取6-31G(d,p)和6-31G(d)两种基组对C6FmH6－ m(m＝1～6)进行了几何优化, 并对优化结构运用B3LYP/6-31G(d,p)方法进行了键能计算, 选用B3LYP-GIAO/6-31＋＋G(d,p)方法进行核无关化学位移(Nucleus-Independent Chemical Shifts, NICS)的计算. 研究表明, 所研究的氟代苯的基态均呈平面几何结构, 6-31G(d,p)基组计算的键长、键角的结果与实验值更加吻合, 其芳香性都较苯的大, 且随取代F数目的增加而增大. 用NBO对分子总NICS及各键对NICS的贡献进行了分解, 结果显示, 氟的pz孤对电子参与六元环π键的形成是使氟代苯分子芳香性变大的主要原因.

关键词: 氟取代苯, 结构, 芳香性, 密度泛函, 核独立化学位移

The geometries and bonding energies were predicted with the hybrid density functional method B3LYP. Bond distances and bond angles predicted with 6-31G(d, p) basis set are closer to the experimental values than those with 6-31G(d) basis set. The geometries of all C6FmH6－m (m＝1～6) are planar. The nuclear independent chemical shift (NICS), calculated using B3LYP-GIAO/6-31＋＋G(d,p), indicates that all fluorinated benzenes are more aromatic than benzene, and the aromaticity increases with the number of F in C6FmH6－m (m＝1～6). The various dissected bond NICSs reveal that the pz lone pair electrons of F atoms play a dominant role in the aromaticity of C6FmH6－m (m＝1～6), and participate in formation of π current of the hexagon.

Key words: fluorinated benzene, structure, aromaticity, density functional theory, NICS