物理化学学报 >> 2011, Vol. 27 >> Issue (09): 2059-2064.doi: 10.3866/PKU.WHXB20110914

理论与计算化学 上一篇    下一篇

咪唑氟硼酸类离子液体熔点与分子内相互作用能的关系

李巍, 戚传松, 吴新民, 荣华, 龚良发   

  1. 北京石油化工学院化学工程学院, 北京 102617
  • 收稿日期:2011-04-26 修回日期:2011-06-29 发布日期:2011-08-26
  • 通讯作者: 李巍 E-mail:liwei77@bipt.edu.cn
  • 基金资助:

    北京市属高等学校人才强教深化计划(PHR201008349)资助项目

Relationship between Melting Point and the Interaction Energy of Alkyl Imidazolium Tetrafluoroborate Ionic Liquids

LI Wei, QI Chuan-Song, WU Xin-Min, RONG Hua, GONG Liang-Fa   

  1. College of Chemical Engineering, Beijing Institute of Petro-chemical Technology, Beijing 102617, P. R. China
  • Received:2011-04-26 Revised:2011-06-29 Published:2011-08-26
  • Contact: LI Wei E-mail:liwei77@bipt.edu.cn
  • Supported by:

    The project was supported by the Training Foundation for Backbone Teachers of Beijing Universities, China (PHR201008349).

摘要: 运用密度泛函理论B3LYP方法及6-311++G(d,p)基组对11种咪唑氟硼酸离子液体进行了研究. 选择相应化合物的离子体系{[XIM][BF4]n}(n-1)- (n=2, 3)作为研究对象, 即研究体系由一个烷基咪唑阳离子XIM+和2-3个BF4-阴离子构成, 对其进行结构优化. 在优化得到的最低能量构型的基础上计算了分子内阳离子与阴离子间的相互作用能, 同时考虑了基组重叠误差的修正. 结果表明所研究离子体系的离子间相互作用能与离子液体的实验熔点之间存在明确的线性关系, 并且所得到的线性方程与氨基酸阳离子型离子液体中存在的线性关系相近. 我们的工作为今后借助量子化学方法设计功能化离子液体提供了一定的理论基础.

关键词: 密度泛函理论, 咪唑氟硼酸盐, 相互作用能, 离子液体, 熔点

Abstract: Eleven types of alkyl imidazolium tetrafluoroborate ionic liquids (ILs) have been investigated using the density functional theory (DFT) B3LYP method together with basis set 6-311++G(d,p). First, we performed geometry optimization of the ion system {[XIM] [BF4]n}(n-1)- (n=2, 3), which is composed of one alkyl imidazolium cation XIM+ and two or three BF4- anions. Then the intramolecular interaction energies were calculated for those structures with the lowest energies, and the basis set superposition error was corrected by the counterpoise method. The relationship between the experimental melting points and the interaction energies was also investigated. A linear correlation was found for the alkyl imidazolium tetrafluoroborate compounds studied, which was also consistent with the linear correlation previously found for amino acid cation based ILs. Our work shows the possibility of designing ILs with the help of quantum chemistry in the future.

Key words: Density functional theory, Imidazolium tetrafluoroborate, Interaction energy, Ionic liquid, Melting point

MSC2000: 

  • O641