液态水中的密度和结构波动的空间相关性:一项比较模拟研究
Felix Sedlmeier1, Dominik Horinek, Roland R Netz
1Physik Department, Technische Universität München, 85748 Garching, Germany.
Journal of the American Chemical Society
|January 18, 2011
概括
模拟显示,液态水是液态水.
科学领域:
- 计算物理学的计算物理.
- 物理化学 物理化学
- 材料科学是一种材料科学.
背景情况:
- 液态水具有复杂的结构性质.
- 了解空间相关性是描述水的行为的关键.
研究的目的:
- 研究液态水中的局部密度和结构秩序之间的空间相关性.
- 为了将模拟结果与实验小角度X射线散射 (SAXS) 数据进行比较.
主要方法:
- 使用各种力场的大规模经典模拟.
- 对密度和结构顺序参数 (四面体,键) 的空间两点相关函数的计算.
主要成果:
- 模拟准确地复制了实验SAXS结构因子S ().
- TIP4P/2005力场显示与S{\displaystyle S{\displaystyle S}q{\displaystyle S{\displaystyle S}q{\displaystyle S{\displaystyle S}q}) 几乎有数量上的一致性.
- 与密度波动相比,结构顺序参数显示的空间相关性较弱.
结论:
- 液体水对密度聚类的倾向明显强于结构聚类.
- 密度的空间相关性并不直接转化为液态水结构的空间相关性.
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