结构秩序与液态水的异常之间的关系
J R Errington1, P G Debenedetti
1Department of Chemical Engineering, Princeton University, New Jersey 08544-5263, USA.
Nature
|February 24, 2001
概括
在水等液体中量化结构秩序是具有挑战性的. 这项研究揭示了一个独特的液态水区域,其中秩序随着压缩而减少,解释了异常性质.
科学领域:
- 物理化学 物理化学
- 材料科学 材料科学 材料科学
- 计算物理 计算物理
背景情况:
- 晶体固体具有明确的结构,与液体和玻璃不同.
- 很难量化液体中的结构顺序,特别是具有键的水.
- 水的异常动力学和热力学特性与其结构有关.
研究的目的:
- 量化理解水中的结构-属性关系.
- 研究水模型中的转换和定向顺序.
- 为了确定水的异常性质的结构基础.
主要方法:
- 水模型的分子动力学模拟.
- 对转换和定向顺序参数的分析.
- 识别结构异常地区.
主要成果:
- 在水中发现了一个结构异常的区域,它以密度依赖的极端顺序为界限.
- 在这个区域内压缩时,顺序会下降,并与翻译和定向顺序相结合.
- 这个区域包含异常扩散和热膨胀的条件.
结论:
- 水中的结构异常被量化并与动力学和热力学特性联系在一起.
- 一连串的异常随着结构秩序的增加而连续发生.
- 这项工作为了解水的独特行为提供了定量框架.
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