由局部顺序参数表示的三个不同的稳定的液态水结构存在的数值证据
1National Institute of Advanced Industrial Science and Technology (AIST), Research Center for Computational Design of Advanced Functional Materials, Central 2, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568, Japan.
The Journal of chemical physics
|October 2, 2024
概括
本研究使用分子模拟和局部顺序参数 (LOPs) 数字验证了三种不同的液态水结构. 这些发现提供了证据表明这些结构是不同的,有助于了解水的结构.
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:
- 不同液态水结构的存在和独特性质,特别是在高温和高压范围内,仍在争论中.
- 之前的实验研究已经提出了三种不同的液态水结构,但除了密度之外,还缺乏明确的区分措施.
研究的目的:
- 通过数值验证三种不同的散装液态水结构的存在.
- 为了确定一个可靠的测量方法,除了密度,以区分这些液态水结构.
- 提供数字证据支持液态水中的结构差异.
主要方法:
- 使用可靠的水分子模型进行了分子模拟.
- 采集了各种冰相 (Ih,III,V,VI) 附近的共存点和三点附近的液体结构样本.
- 通过用于识别顺序参数 (MASSIOP) 的分子组结构学习包识别和利用局部顺序参数 (LOPs).
主要成果:
- 一个选定的局部顺序参数 (LOP) 准确地区分了三种拟议的稳定液态水结构.
- 数字证据证实,液态水中的这些独特的结构顺序存在显著差异.
- 对每个液态水结构的确定区域被映射到相位图上.
结论:
- 这项研究提供了强有力的数值证据,证明了三种不同的稳定液态水结构的存在.
- 地方秩序参数 (LOP) 作为区分这些结构的有效工具.
- 这些发现与之前对液态水结构的实验观测一致,并支持这些观测.
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