EMIM离子液体离子簇模型的量子化学计算  

Quantum Chemistry Calculations of Ion Cluster Models of EMIM Ionic Liquids

作　　者：李巍[1] 张静[2] 戚传松[1] 

机构地区：[1]北京石油化工学院化学工程学院,北京102617 [2]中国科学院大学材料科学与光电技术学院,北京100049

出　　处：《物理化学学报》2015年第9期1690-1698,共9页Acta Physico-Chimica Sinica

基　　金：北京石油化工学院优秀学科带头人培育计划(BIPT-BPOAL-2014)资助项目~~

摘　　要：以1-乙基-3-甲基咪唑(EMIM)卤化物、氟硼酸盐、三溴化物和二碘溴酸盐、氯铝酸和溴铝酸盐等不同种类EMIM离子液体为研究对象,对多阳离子、多阴离子的离子簇模型进行了量子化学计算研究.首先在B3LYP/6-311++G(d,p)水平上(I使用6-311G(d,p)基组)对{[EMIM]Xn}(n–1)–(X=Cl,Br,I,BF4,Al Cl4,Al Br4,Br3,IBr I,FHF;n=2,3)和{[EMIM]2Xn'}(n'–2)–(n'=3,4,5)离子簇进行构型优化,并对卤化物和氟硼酸盐进行了振动光谱计算.结果表明所采用理论模型在键长、键角等结构参数及红外振动光谱方面均与实验结果符合较好.同时对不同离子簇模型中阴、阳离子间相互作用能与实验熔点之间的关系进行了研究,发现采用{[EMIM]2Xn'}(n'–2)–模型时EMIM离子液体实验熔点与阴、阳离子间相互作用能之间呈现近线性关系.Different types of 1-ethyl-3-methylimidazolium（EMIM） ionic liquid compounds, including halides,tetrafluoroborate, tribromide, diiodobromate, chloroaluminate, and bromine aluminate, have been investigated using quantum chemical calculations. First, geometry optimizations of the ion systems, including{[EMIM]Xn}（n–1）–（X = Cl, Br, I, BF4, Al Cl4, Al Br4, Br3, IBr I, FHF; n = 2, 3） and {[EMIM]2Xn＇}（n＇–2）–（n＇ = 3, 4, 5）, were performed using the density functional theory（DFT） B3 LYP method together with the 6-311＋＋G（d,p）（6-311G（d,p） for I） basis set. The vibrational spectra were also calculated for the EMIM halides and tetrafluoroborate. The obtained structures and vibrational spectra were consistent with experimental results. In addition, a linear correlation between melting point and interaction energy was obtained for the{[EMIM]2Xn＇}（n＇–2）– models of the compounds studied.

关 键 词：密度泛函理论 咪唑离子液体 相互作用能 离子簇 熔点 

分 类 号：O645.1[理学—物理化学]