Solvatochromic Parameters and Preferential Solvation Behavior for Binary Mixtures of 1,3-Dialkylimidazolium Ionic Liquids with Water  

1,3-二烷基咪唑离子液体．水二元混合物的溶致显色参数和优先溶剂化行为

作　　者：丁珊[1] 魏立纲[1] 李坤兰[1] 马英冲[1] 丁珊;魏立纲;李坤兰;马英冲(大连工业大学轻工与化学工程学院,大连116034)

机构地区：[1]大连工业大学轻工与化学工程学院,大连116034

出　　处：《Chinese Journal of Chemical Physics》2016年第4期497-507,I0002,共12页化学物理学报（英文）

摘　　要：Binary mixtures of 1,3-dialkylimidazolium based ionic liquids （ILs） and water were selected as solvent systems to investigate the solute-solvent and solvent-solvent interactions on the preferential solvation of solvatochromic indicators at 25 ℃. Empirical solvatochromic pa- rameters, dipolarity/polarizability （π^＊）, hydrogen-bond donor acidity （α）, hydrogen-bond acceptor basicity （β）, and Reichardt＇s polarity parameters （ET^N） were measured from the ultraviolet-visible spectral shifts of 4-nitroaniline, 4-nitroanisole, and Reichardt＇s dye. The solvent properties of the IL-water mixtures were found to be influenced by IL type and IL mole fraction （XIL）. All these studied systems showed the non-ideal behavior. The max- imum deviation to ideality for the solvatochromic parameters can be obtained in the XIL range from 0.i to 0.3. For most of the binary mixtures, the π^＊ values showed the synergistic effects instead of the ETN, α and β values. The observed synergy extent was dependent on the studied systems, such as the dye indicator and IL type. A preferential solvation model was utilized to gather information on the molecular interactions in the mixtures. The dye indicator was preferentially solvated on the following trend： IL〉IL-water complex〉water.

关 键 词：Solvatochromic parameters Preferential solvation Ionic liquid WATER 

分 类 号：O4[理学—物理]