烷基吡啶及氯化铝正负离子结构的密度泛函研究  

Study of density functional theory on N-alkylpyridium cations and aluminium chloride anions

作　　者：李鸿雁[1] 王大喜[1] 窦荣坦[1] 高金森[1] 

机构地区：[1]中国石油大学重质油国家重点实验室,北京102249

出　　处：《分子科学学报》2006年第5期306-311,共6页Journal of Molecular Science

基　　金：国家自然科学基金资助项目(29734130);中国石油天然气集团公司中青年创新基金资助项目(03E7017);北京市教委共建项目资助项目(XK114140479)

摘　　要：采用量子化学密度泛函方法对N-烷基吡啶阳离子和阴离子AlCl4-,Al2Cl7-和Al3Cl10-进行了全优化计算,得到了阴阳离子的几何构型和净电荷分布.计算发现,吡啶环上的电子数符合4n+2规则,具有芳香性.吡啶阳离子的LUMO轨道主要由环上原子的2pz所贡献,是反键π分子轨道.AlCl4-,Al2Cl7-和Al3Cl10-的HOMO轨道主要由Cl原子的2px所贡献.推测吡啶阳离子的LUMO与阴离子的HOMO相互作用形成离子液体分子.On the basis of density functional theory （DFT） method of quantum chemistry, calculations of some N-alkylpyridinium cations and chloroaluminate anions were conducted to obtain the geometries of thses ions, the atomic net charge of AI and CI atoms and bridge CI in AlCl4^-,Al2Cl7^- and Al3Cl10^- species. The number of electrons of pyridinium cation rings obeys the 4n＋2 rule, and these cation rings possess aromaticity. The 2px orbitals made contributions to the LUMOs of cations which are anti-π molecular orbitals. The HOMOs of AlCl4^-,Al2Cl7^- and Al3Cl10^- are contributed by 2px orbitals of CI atoms. It is predicted that the LUMOs of cations interact with the HOMOs of the anions to form ionic liquid molecules.

关 键 词：离子液体 几何构型 密度泛函 阴离子 阳离子 

分 类 号：O640[理学—物理化学]