Structure of water under subcritical and supercritical conditions studied by solution X-ray diffraction
Structure of water under subcritical and supercritical conditions studied by solution X-ray diffraction
复制标题
通过溶液 X 射线衍射研究亚临界和超临界条件下水的结构
DOI：
10.1039/cs9972600041
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发表时间：
1997
影响因子：
46.2
通讯作者：
T. Yamaguchi
中科院分区：
文献类型：
--
作者：
H. Ohtaki;T. Radnai;T. Yamaguchi
本文综述了用X射线衍射和中子衍射研究亚临界和超临界条件下水和电解质水溶液的结构，并将实验结果与计算机模拟结果进行了比较。通过拉曼光谱数据讨论了高温高压下水分子中氢键的存在，并将超临界水分为三类：（a）低密度水，（B）中密度水，和（c）高密度水，因为密度是描述亚、超临界水性质的一个非常重要的热力学量，从水的变化-水分子间距离和水的配位数与温度和压力，特别是与密度在HTHP，作者得出结论，紧凑的四面体状水结构被分解，长距离水-水相互作用随着温度和压力增加，他们提出了一个水模型：在超临界条件下，水由小的团簇、小得多的聚集体如低聚物、甚至单体气体状水分子组成。
Stuctures of water and aqueous electrolyte solutions under sub-and super-critical conditions studied mainly by X-ray diffraction and also by neutron diffraction are reviewed and the experimental results are compared with those reported by using computer simulations. Some Raman spectroscopic data are included for discussing the existence of hydrogen bonds in water at high temperature and high pressures (HTHPs).The authors propose a classification of supercritical water into three categories: (a) low density water, (b) medium density water, and (c) high density water, because density is a very important thermodynamic quantity to describe properties of sub- and super-critical water.From changes in the water–water intermolecular distance and the coordination number of water with temperature and pressure, and especially with density at HTHP, the authors conclude that the compact tetrahedral-like water structure is decomposed and long-distance water–water interactions increase with temperature and pressure, and they propose a model for water: under supercritical conditions water consists of small clusters, much smaller aggregates such as oligomers, and even monomeric gas-like water molecules.