Understanding the elementary hydration dynamics of the ions and their couplings with the aqueous environments is important for researches in fields including energy, molecular biology, biomedical sciences, and chemical reactions. The concept of hydration shell is ubiquitously used to rationalize the differences of water behavior near the ions with respect to those in the bulk water. One intriguing issue, however, is to decide the spatial range of these hydration shells. Different experimental spectroscopic techniques such as the femtosecond infrared at high frequency and optical Kerr effect, dielectric relaxation, as well as terahertz measurements at low frequency often give controversial indications on this matter. As the optical transition observables provided by the spectroscopic measurements only indirectly reflect the real‐space structure and dynamics information, the theoretical modeling of these signals is often desired in order to reveal the underlying physics in each of these measurements, and to understand the aforementioned apparent controversy. In this review, we outline recent progresses in the theoretical modeling of water dynamics around the ions and ionic moieties and the related vibrational spectroscopy, especially on the femtosecond infrared related single molecular water reorientation and the low‐frequency vibrational spectra related collective water dynamics.

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离子对水氢键网络动力学的影响：理论和计算光谱学的观点

理解离子的基本水合动力学及其与水环境的耦合对包括能源，分子生物学，生物医学和化学反应等领域的研究非常重要。水合壳的概念普遍用于合理化离子附近的水行为与散装水中的离子之间的行为差​​异。然而，一个有趣的问题是确定这些水合壳的空间范围。不同的实验光谱技术，例如高频率的飞秒红外和光学克尔效应，介电弛豫以及低频率的太赫兹测量，常常在此问题上引起争议。由于光谱测量提供的光学跃迁观测值仅间接反映了真实空间的结构和动力学信息，因此通常需要对这些信号进行理论建模，以揭示每个测量中的基本物理原理，并理解上述明显现象。争议。在这篇综述中，我们概述了围绕离子和离子部分的水动力学理论模型以及相关的振动光谱学的最新进展，尤其是在飞秒红外相关的单分子水重新定向以及与低频振动光谱有关的集体水动力学方面的最新进展。并了解上述明显的争议。在这篇综述中，我们概述了围绕离子和离子部分的水动力学理论模型以及相关的振动光谱学的最新进展，尤其是在飞秒红外相关的单分子水重新定向以及与低频振动光谱有关的集体水动力学方面的最新进展。并了解上述明显的争议。在这篇综述中，我们概述了围绕离子和离子部分的水动力学理论模型以及相关的振动光谱学的最新进展，尤其是在飞秒红外相关的单分子水重新定向以及与低频振动光谱有关的集体水动力学方面的最新进展。