Ionic Liquids with Symmetric Diether Tails: Bulk and Vacuum-Liquid Interfacial Structures
Ionic Liquids with Symmetric Diether Tails: Bulk and Vacuum-Liquid Interfacial Structures
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DOI：
10.1021/acs.jpcb.6b09148
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发表时间：
2017-01-12
影响因子：
3.3
通讯作者：
Margulis, Claudio J.
中科院分区：
文献类型：
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作者：
Hettige, Jeevapani J.;Amith, Weththasinghage D.;Margulis, Claudio J.
在双亲性离子液体中，无论是阳离子还是阴离子都具有中等长的烷基尾巴，它们在体积和界面上的行为都在很大程度上得到了很好的理解。不太清楚的是，当正离子和阴离子都具有非极性的尾巴时，会发生什么，比如在醚功能的情况下。本文讨论了C2OC2OC2-mim(+)/C2OC2OC2-OSO3在体和真空界面的结构特征。我们发现真空界面只影响纳米尺度。这与我们最近在（J.物理学）中发现的情况相反。化学。列托人。等电子C[8]-mim(+)/C[8]- oso3 -的界面效应，2016,7(19),3785-3790。有趣的是，具有双醚尾功能的离子在真空界面上仍然倾向于尾部向外的取向，而体相保留了带电网络和尾部之间的交替，这在双亲性离子液体中是常见的。然而，这种交替不太明确，并导致在体积液体结构函数中第一尖锐衍射峰明显减弱。
The behavior in the bulk and at interfaces of biphilic ionic liquids in which either the cation or anion possesses moderately long alkyl tails is to a significant degree well understood. Less clear is what happens when both the cation and anion possess tails that are not apolar, such as in the case of ether functionalities. The current article discusses the structural characteristics of C2OC2OC2-mim(+)/C2OC2OC2-OSO3 in the bulk and at the vacuum interface. We find that the vacuum interface affects only the nanometer length scale. This is in contrast to what we have recently found in (J. Phys. Chem. Lett., 2016, 7 (19), 3785-3790) for isoelectronic C[8]-mim(+)/C[8]-OSO3-, where the interface effect is long ranged. Interestingly, ions with the diether tail functionality still favor the tail-outward orientation at the vacuum interface and the bulk phase preserves the alternation between charged networks and tails that is commonly observed for biphilic ionic liquids. However, such alternation is less well-defined and results in a significantly diminished first sharp diffraction peak in the bulk liquid structure function.