NMR studies on the molecular dynamics of hydrogen bonded liquids in nanoscopic confinements

在这个项目中，我们打算利用核磁共振实验来研究纳米限制下的氢键液体。特别是，考虑到复杂相行为的可能性，我们将确定受限液体的分子动力学作为限制几何的大小、亲水性和软性的函数。在工程实施过程中，从简单流体到复杂流体，从均相约束到非均质约束，所研究的流体系统将变得更加复杂。这样，知识从简单的模型到精细的材料的转移将得到保证。首先，研究将集中在大小、亲水性和柔软性明确的限制条件下的水-醇混合物。这种方法将使我们对液体动力学对界面处潜在微相分离背景下的限制几何性质的依赖性有一个基本的理解。之后，计划考虑日益复杂的宾主系统。最后，我们将处理由大分子聚集器提供的无序基质中与水和共溶剂一起驻留的蛋白质。对于后一种体系，需要了解短期动力学和远程动力学的关系以及蛋白质和溶剂运动的耦合，这对生物功能起着决定性的作用。我们的研究旨在开发核磁共振的能力。该方法的同位素选择性将使我们能够单独确定对所考虑的混合物的各个组分的分子动力学的限制效应。在这样做时，它将被利用，当结合各种核磁共振技术时，可以在宽动态范围和宽温度区间内进行运动。此外，我们将利用核磁共振实验，特别是刺激回声实验，不仅提供对速率的见解，而且还提供分子动力学的机制。最后，我们将利用在均匀和非均匀磁场中进行核磁共振实验时，研究不同长度尺度上的运动的可能性。

In this project, we intend to investigate hydrogen bonded liquids in nanoscopic confinements using NMR experiments. In particular, we will ascertain the molecular dynamics of the confined liquids as a function of the size, hydroaffinity, and softness of the confining geometry, considering the possibility of complex phase behavior. In the course of the project, the complexity of the studied guesthost systems will be increased, proceeding from simple to complex fluids and from homogeneous to heterogeneous confinements. In this way, knowledge transfer from simple models to elaborate materials will be ensured. At the beginning, the studies will focus on water-alcohol mixtures in confinements of well-defined size, hydroaffinity, and softness. This approach will allow us to develop a basic understanding of the dependence of liquid dynamics on the properties of the confining geometry against the background of potential microphase segregation at interfaces. Afterwards, it is planned to consider increasingly complex guest-host systems. At the end, we will deal with proteins residing together with water and cosolvent in a disordered matrix provided by macromolecular crowders. For the latter systems, the relations of short-ranged and long-ranged dynamics and the couplings of protein and solvent motions are to be understood, which play a decisive role for biological functions. Our studies intend to exploit the capabilities of NMR. The isotope selectivity of the method will allow us to separately ascertain confinement effects for the molecular dynamics of the individual components of the considered mixtures. In doing so, it will be utilized that motions in wide dynamic ranges and broad temperature intervals are accessible when combining various NMR techniques. Moreover, we will make use of the fact that NMR experiments, in particular, stimulated-echo experiments, provide insights into not only the rates, but also the mechanisms for molecular dynamics. Finally, we will take advantage of the possibility to investigate motions on various length scales, when performing NMR experiments in both homogeneous and inhomogeneous magnetic fields.