Study of structure and viscosity correlation in novel ionic liquids.

Ionic Liquids (ILs) have three distinct structural motifs: adjacency correlations, charge alterations, and polar-apolar alterations. Each of these motifs has its own relaxation. These motifs are associated with different length scales and are described by the peaks associated with the structure-function S(Q) and its time-dependent version S(Q,t). X-ray scattering experiments and MD simulations can probe the S(Q). On the other hand, QENS can be used to probe the variation of local dynamics over different length scales associated with the process of charge blurring within the charge networks. The amphiphilic ions show nanoscale domain segregation leading to regions with different local frictions is one of the primary motivations for us to explore neutron scattering methods to measure the dynamics on specific length scales using QENS experiments which addressed by the variation of measured diffusivities across the length scales that define the charge-ordering of these ionic liquids,
Experiments show changing one atom or functional group of IL anion or cation results in a noticeable change in viscosity, while the liquid structure is largely unaffected. By combining NMR measurements together with molecular dynamics from QENS and the measured and calculated liquid factors, we plan to resolve the connections between ILs structure from glassy-state to liquid state, dynamics, and ion self-diffusivities and how these combines to determine the bulk liquid shear viscosities.

离子液体（Ionic Liquids, ILs）具有三种独特的结构基序：邻接关联、电荷变化和极性-非极性变化。每种基序均具有其独特的弛豫过程，且与不同长度尺度相关联，可通过结构函数S(Q)及其时间依赖形式S(Q,t)的相关峰来描述。X射线散射实验和分子动力学模拟（Molecular Dynamics simulations, MD）可探测S(Q)；另一方面，准弹性中子散射（Quasi-Elastic Neutron Scattering, QENS）可用于探测电荷网络内电荷模糊过程相关的不同长度尺度上的局域动力学变化。两亲离子表现出纳米尺度畴分离，形成具有不同局域摩擦的区域——这是我们探索中子散射方法的主要动机之一，旨在通过QENS实验测量特定长度尺度上的动力学，而该实验可通过跨定义离子液体电荷有序化的长度尺度的实测扩散系数变化来解决这一问题。

实验表明，改变IL阴离子或阳离子的单个原子或官能团会导致粘度发生显著变化，而液体结构基本不受影响。通过结合核磁共振（Nuclear Magnetic Resonance, NMR）测量、QENS的分子动力学数据以及实测与计算的液体因子，我们计划解析IL从玻璃态到液态的结构、动力学与离子自扩散系数之间的关联，以及这些因素如何共同决定本体液体的剪切粘度。