Local order in aqueous lithium chloride solutions as studied by X-ray scattering and molecular dynamics simulations
Local order in aqueous lithium chloride solutions as studied by X-ray scattering and molecular dynamics simulations
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DOI：
10.1016/j.molstruc.2006.10.017
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发表时间：
2007-06-30
影响因子：
3.8
通讯作者：
Nasr, Salah
中科院分区：
文献类型：
--
作者：
Bouazizi, Salah;Nasr, Salah
对纯水和含水氯化锂溶液在0.5、1.5、3和4摩尔摩尔盐浓度下进行了x射线散射和分子动力学（MD）模拟。实验和理论结果都表明，与纯流体相比，液态水中的氢键减少。MD结果还表明，随着盐浓度的增加，阳离子周围的水化数减少；同时，接触离子对的比例增加，溶剂分离离子对的比例减少。通过考虑刚性SPC水模型和Lennard-Jones势，从MD模拟中推导出的系统中的局部阶数与从x射线数据中提取的局部阶数直接对应。各系统的理论对相关函数与实验对相关函数具有较好的一致性。(c) 2006 Elsevier B.V.版权所有
X-ray scattering and molecular dynamics (MD) simulations are carried out on pure water and aqueous lithium chloride solutions at four salt concentrations 0.5, 1.5, 3 and 4 molal. Both experimental and theoretical results indicate a decrease of hydrogen bonding in liquid water as compared with pure fluid. MD results also show that the hydration number around the cation decreases with increasing salt concentration; simultaneously the fraction of contact ion pairs increases and that of solvent-separated ion pairs decreases. The local order in the systems, as deduced from MD simulation by considering the rigid SPC water model and the Lennard-Jones potential, is directly confronted with that extracted from X-ray data. A good agreement is shown between the theoretical and experimental pair correlation functions of each system. (c) 2006 Elsevier B.V. All rights reserved.