离子对水结构的影响

Effects of Ions on Structure of Liquid Water

液态水中广泛存在的氢键网络使其作为一种结构性很强的液体在自然界中发挥着独一无二的作用。电解质溶于水中后,以水合离子形式存在,离子附近强大的电场使水合层中的偶极水分子发生重排,这些水分子的结构与本体水的结构存在差异。一个多世纪以来,科学家做了大量关于离子对水结构影响的研究。本文从静态谱学和溶剂动力学两方面综述了离子对水结构影响的研究进展,概括了水中氢键的研究情况,并就离子对水结构影响在生物化学方向的重大意义-Hofmeister效应作了解释。

Water is a highly structured liquid substance due to an extensive network of hydrogen bonds,which plays a unique role in the world.Electrolytes dissolved in water dissociate into ions that are hydrated,the large electric field around the ions causes the dipolar water molecules to rearrange themselves in the hydration shells,structure of water around the ions differing from that in bulk water.There has been a great deal of studies on the effects of ions on the structure of liquid water for more than a century.The progresses of the influences of ions on water structure researched in both static spectroscopic and solvent dynamics aspects were summarized.Hydrogen bonds in liquid water were outlined and the biochemical significance of ion effects on water structure（Hofmeister effect） was also expatiated.