使用完全ab initio模拟的水的固有结构
Shuo Cao1, Gang Zhao1, Dehua Wang1
1School of Physics and Optoelectronic Engineering, Ludong University, Yantai 264025, P. R. China. gzhao19800209@126.com.
Physical chemistry chemical physics : PCCP
|July 11, 2023
概括
研究人员使用先进的模拟来揭示水中的三个不同的局部结构. 这些发现解释了水的最大密度,并支持水的混合模型.
科学领域:
- 物理化学 物理化学
- 计算化学计算化学
- 材料科学 材料科学 材料科学
背景情况:
- 了解液态水的复杂结构对于各种科学学科至关重要.
- 以前的模型一直在努力充分解释水的异常性质,例如其最大密度.
研究的目的:
- 通过*ab initio*分子动力学研究液态水的固有局部结构.
- 阐明这些结构的温度依赖性及其在水的特性中的作用.
主要方法:
- 完全使用*ab initio*分子动力学模拟.
- 使用SCAN函数用于准确的电子结构计算.
- 根据第二个氧气协调的转化顺序对当地水结构进行分类.
主要成果:
- 在水中确定了三种不同的局部结构:结构I (无序),结构II (类似冰II/V) 和结构III (类似冰III).
- 在液态水结构和晶体冰之间观察到四面体定向和结合角度分布的差异,尽管它们的转换顺序相似.
- 证明了这些结构之间的竞争解释了水的最大密度.
结论:
- 液态水和晶体冰,虽然共享一些翻译顺序,但具有根本不同的局部原子结构.
- 拟议的水混合模型,包括结构I,II和III,得到了初始模拟证据的支持.
- 这些发现为水的独特行为及其潜在的分子机制提供了更深入的理解.
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