Department of Chemistry, University of Burgos, 09001 Burgos, Spain.
J Phys Chem B. 2012 Mar 1;116(8):2526-37. doi: 10.1021/jp212258b. Epub 2012 Feb 17.
We report in this work a combined experimental and computational study on the molecular level structuring of binary ionic liquid mixtures comprising pyridium cations. The effect of anions on liquid structure was analyzed from the mixing (mixture 1) of [b3mpy][BF(4)] and [b3mpy][N(CN)(2)] ionic liquids, in the full composition range, leading to [b3mpy]BF(4)N(CN)(2) mixed ionic liquids. The effect of the length of alkylic chains in cations was studied with mixtures (mixture 2) of [b3mpy][BF(4)] and [o3mpy][BF(4)] ionic liquids, also studied in the full composition range, leading to b3mpyo3mpy[BF(4)] ionic liquids. Fourier transform infrared-attenuated total reflection spectra were recorded and analyzed as a function of anionic and cationic composition for the two studied mixture types. Classical molecular dynamics simulations were also performed for mixtures 1 and 2 as a function of anionic and cationic composition. The reported experimental and computational results show that the properties of the studied mixed systems change in an almost linear way, leading to almost ideal mixtures from the thermodynamic viewpoint, and thus pointing to simple dilution effects of the involved ions controlling the mixture properties.
在这项工作中，我们报告了一项关于包含吡啶阳离子的二元离子液体混合物在分子水平上结构的实验和计算研究。从 [b3mpy][BF(4)] 和 [b3mpy][N(CN)(2)] 离子液体的混合（混合物 1）的角度分析了阴离子对液体结构的影响，在全组成范围内，导致 [b3mpy]BF(4)N(CN)(2) 混合离子液体。还研究了阳离子中烷基链长度的影响与 [b3mpy][BF(4)] 和 [o3mpy][BF(4)] 离子液体的混合物（混合物 2），同样在全组成范围内，导致 b3mpyo3mpy[BF(4)] 离子液体。记录了傅里叶变换红外衰减全反射光谱，并作为两种研究混合物类型的阴离子和阳离子组成的函数进行了分析。还对混合物 1 和 2 进行了经典分子动力学模拟，作为阴离子和阳离子组成的函数。报告的实验和计算结果表明，所研究的混合体系的性质以几乎线性的方式变化，从热力学角度来看，形成几乎理想的混合物，因此表明参与离子的简单稀释效应控制混合物的性质。
