在低密度和高密度无形冰之间的无形冰的连续性
Ali Eltareb1,2, Gustavo E Lopez3,4, Nicolas Giovambattista5,6,7
1Department of Physics, Brooklyn College of the City University of New York, Brooklyn, NY, 11210, USA. ali.eltareb@brooklyn.cuny.edu.
Communications chemistry
|February 20, 2024
概括
计算机模拟揭示了一连续的无形冰,包括中间的无形冰 (IA),由等离子冷却产生. 在125 MPa时产生的IA非常类似于中密度无形冰 (MDA),这表明MDA并非独一无二.
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:
- 无形冰通常被分为低密度 (LDA) 或高密度 (HDA) 形式.
- 最近的实验通过球磨产生了中密度无形冰 (MDA),使水相图的理解变得复杂.
- 各种无形冰密度的存在和形成途径需要进一步研究.
研究的目的:
- 用计算机模拟研究不同压力条件下的无形冰的形成.
- 探索通过等离子冷却和压缩/解压产生无形冰的密度范围和结构性质.
- 了解潜在能源景观中的LDA,HDA,MDA和新发现的中间形态冰 (IA) 之间的关系.
主要方法:
- 在同位体冷却和同热压缩/解压下对水进行了广泛的计算机模拟.
- 分析了产生的无形冰相的密度和结构特征.
- 利用潜在能源景观 (PEL) 形式主义来解释不同形态冰的性质和稳定性.
主要成果:
- 异构体冷却可以产生连续范围的无形冰 (IA),密度介于LDA和HDA之间,取决于施加的压力.
- 在大约125MPa时产生的中间无形冰 (IA) 呈现密度和结构相似性,与实验生成的MDA.
- 在PEL中,LDA和HDA占据了不同的区域,而IA则在分隔它们的中间区域形成.
结论:
- 发现无形冰的连续性挑战了离散的LDA/HDA分类.
- 中密度无形冰 (MDA) 可能不是单一的阶段,而是在特定条件下形成的中间无形冰 (IA) 的代表.
- 潜在能源景观为了解不同无形冰密度之间的形成和关系提供了一个框架.
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