曾冬雷,冯飙,宋嘉文,范利武

• 1:浙江大学热工与动力系统研究所
• 2:浙江大学能源清洁利用国家重点实验室

摘要(Abstract)：

为了分析超临界水的密度不均匀性,对不同温度(666、700和800 K)的超临界水体系进行分子动力学模拟,研究了在较大的密度范围内(0.4ρ_c～2ρ_c,ρ_c为水的临界密度)超临界水中氢键的数量、键能与空间分布规律。采用经典的TIP4P/2005水分子模型在正则系综下对1 000个水分子进行模拟。结果表明:随着超临界水密度的增大,氢键的数量、平均键能以及氢键空间分布的均匀性均增大。由于密度较低时水分子形成局部团聚,导致氢键在空间上也存在局部团聚现象。在较高的温度下,氢键的数量与平均键能均较低,但其键能大小在空间上分布得较为均匀。对超临界水中氢键特性及其空间分布的密度相关性的定量分析有助于深入理解超临界水密度不均匀性的微观机制。

关键词(KeyWords)： 超临界水;密度;氢键;分子动力学模拟

Abstract:

Keywords:

基金项目(Foundation): 国家自然科学基金(51776184)

作者(Author): 曾冬雷,冯飙,宋嘉文,范利武

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