Hydrogen bonding (H-bonding) is an important and very general phenomenon. H-bonding is part of the basis of life in DNA, key in controlling the properties of water and ice, and critical to modern applications such as crystal engineering, catalysis applications, pharmaceutical and agrochemical development. H-bonding also plays a significant role for many ionic liquids (IL), determining the secondary structuring and affecting key physical parameters. ILs exhibit a particularly diverse and wide range of traditional as well as non-standard forms of H-bonding, in particular the doubly ionic H-bond is important. Understanding the fundamental nature of the H-bonds that form within ILs is critical, and one way of accessing this information, that cannot be recovered by any other computational method, is through quantum chemical electronic structure calculations. However, an appropriate method and basis set must be employed, and a robust procedure for determining key structures is essential. Modern generalised solvation models have recently been extended to ILs, bringing both advantages and disadvantages. QC can provide a range of information on geometry, IR and Raman spectra, NMR spectra and at a more fundamental level through analysis of the electronic structure.

氢键（H-bonding）是一种重要且非常普遍的现象。氢键是 DNA 生命基础的一部分，是控制水和冰性质的关键，对于晶体工程、催化应用、制药和农用化学品开发等现代应用也至关重要。氢键对于许多离子液体 (IL) 也起着重要作用，决定二级结构并影响关键物理参数。IL 表现出特别多样化和广泛的传统以及非标准形式的氢键，特别是双离子氢键很重要。了解离子液体中形成的氢键的基本性质至关重要，而获取此信息的一种方法是通过量子化学电子结构计算，而这种信息无法通过任何其他计算方法来恢复。然而，必须采用适当的方法和基础集，并且确定关键结构的稳健程序至关重要。现代广义溶剂化模型最近已扩展到离子液体，带来了优点和缺点。QC 可以提供一系列有关几何形状、红外光谱和拉曼光谱、核磁共振光谱的信息，并通过电子结构分析提供更基础的信息。