化工学报 ›› 2019, Vol. 70 ›› Issue (S2): 85-93.DOI: 10.11949/0438-1157.20190431

• 热力学 • 上一篇    下一篇

己基乙二胺-TFS型质子化离子液体与水分子间氢键相互作用的研究

郑勋1(),徐宇1,花儿1,2()   

  1. 1. 北方民族大学化学与化学工程学院,宁夏 银川 750021
    2. 北方民族大学国家民委化工技术基础重点实验室,宁夏 银川 750021
  • 收稿日期:2019-04-26 修回日期:2019-07-10 出版日期:2019-09-06 发布日期:2019-09-06
  • 通讯作者: 花儿
  • 作者简介:郑勋(1995—),男,硕士研究生,544410274@qq.com
  • 基金资助:
    北方民族大学科技创新类重点科研项目(2019 KJ13)

Water and hydrogen bonding study on protic ionic liquids composed of hexylethylenediamine cation and trifluoromethanesulfonate anion

Xun ZHENG1(),Yu XU1,Er HUA1,2()   

  1. 1. College of Chemistry and Chemical Engineering, North Minzu University, Yinchuan 750021, Ningxia, China
    2. Key Laboratory of Chemical Engineering and Technology, State Ethnic Affairs Commission, North Minzu University, Yinchuan 750021, Ningxia, China
  • Received:2019-04-26 Revised:2019-07-10 Online:2019-09-06 Published:2019-09-06
  • Contact: Er HUA

摘要:

通过前期实验研究,己基乙二胺-三氟甲磺酸([HHex][TFS])型质子化离子液体(protic ionic liquid,PIL)的极性部位具有两个氨基,亲水性较强,能够与水混溶90%(质量)(H2O/ PIL)以上。因此利用密度泛函理论(density functional theory,DFT),在M06-2X/6-311G(d,p)的水平下,对 [HHex][TFS]与H2O分子间形成的氢键作用进行了研究。设计了[HHex][TFS]分别与nH2O (n = 1, 2, 6) 相结合的构型,并得到了较稳定构型共8种(S1~S8),计算了其分子间的相互作用能(ΔE 0 BSSE)、分子振动频率(Δν)、二阶微扰能、电子密度(ρ c)以及Laplace值(?2 ρ c)。分析结果显示,[HHex][TFS]与水分子间形成了较强的氢键,[HHex][TFS]与H2O结合数量增加,构型中氢键相互作用增强,即S4(n=1)<S6(n=2)<S8(n=6)。

关键词: 质子化离子液体, 水分子, 氢键作用, 密度泛函理论

Abstract:

The protic ionic liquid (PIL) comprising with hexylethylenediaminium (HHex) cation and trifluoromethane sulfonate (TFS) anion forming [HHex][TFS] is hydrophilic and highly miscible with water ( H2O /PIL above 90%(mass)) as there are two amines in the polar group. Therefore, in this study, the hydrogen bonding interaction between [HHex][TFS] and water molecules was investigated using the density functional theory (DFT) at M06-2X/6-311G (d,p) level, the configurations of [HHex][TFS]-nH2O (n= 1, 2, 6) S1-S8 were designed and optimized . The results of molecular interaction (ΔE 0 BSSE), vibration spectra (Δν), the second-order perturbation (E (2)), and electron density (ρ c) and Laplace value (?2 ρ c) show that the hydrogen bonding interaction increase with increasing the water content: S4 (n= 1)<S6 (n= 2)<S8 (n= 6).

Key words: protic ionic liquids, H2O, hydrogen bonding, density functional theory

中图分类号: