Alkyl Chain Length Dependence of Backbone-to-Backbone Distance in Polymerized Ionic Liquids: An Atomistic Simulation Perspective on Scattering
Alkyl Chain Length Dependence of Backbone-to-Backbone Distance in Polymerized Ionic Liquids: An Atomistic Simulation Perspective on Scattering
复制标题
聚合离子液体中主链至主链距离的烷基链长度依赖性：散射的原子模拟视角
DOI：
10.1021/acs.macromol.6b02708
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发表时间：
2017
期刊：
影响因子：
5.5
通讯作者：
S. Paddison
中科院分区：
文献类型：
--
作者：
Hongjun Liu;S. Paddison
聚合离子液体（polyILs）中的主链-主链相关长度表现为散射曲线中的低q峰，其随着烷基链长度的增加而增加，伴随着不断增长的非极性域尺寸。理解相关长度对侧链烷基链长度的依赖性对于有效地设计用于电化学应用的聚离子液体是至关重要的。在此，广泛的原子分子动力学模拟的一个完整的同源系列的聚（n-烷基乙烯基咪唑双（三氟甲基磺酰基）酰亚胺），聚（CnVim Tf 2N）（n = 2-8），已经进行了调查的液体结构，强调散射。同位素标记的中子散射提供了更通用的方法来检查本征结构，但不同的同位素标记的中子和X射线散射数据不一定会导致低q峰的相同位置。这样一个意想不到的后果有一个不平凡的影响利用散射实验。
The backbone-to-backbone correlation length in polymerized ionic liquids (polyILs) manifested as the low-q peak in scattering profiles increases with increasing alkyl chain length, concomitant with ever-growing nonpolar domain size. Understanding the dependence of the correlation length on the pendant alkyl chain length is crucial to effectively designing polyILs for electrochemical applications. Herein, extensive atomistic MD simulations for a complete homologous series of poly(n-alkylvinylimidazolium bis(trifluoromethylsulfonyl)imide), poly(CnVim Tf2N) (n = 2–8), have been carried out to investigate the liquid structure with emphasis on scattering. Neutron scattering with isotopic labeling affords more versatile ways to vet the intrinsic structure, but different isotopically labeled neutron and X-ray scattering data do not necessarily lead to the same position of the low-q peaks. Such an unintended consequence has a nontrivial implication on exploitation of scattering experiments.