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来自NMR自旋格子放松氧化玻璃中的相关离子跳跃的避风港比率

Sabyasachi Sen¹

¹Department of Materials Science and Engineering, University of California at Davis, Davis, California 95616, USA.

The Journal of chemical physics

|September 19, 2025

概括

这项研究显示,在玻璃离子运输中, Haven比率 (HR) 和拉伸指数 (β) 之间大致相等. 这一发现为超冷液体和玻璃中的离子流动性提供了新的见解.

科学领域:

材料科学材料科学材料科学
物理化学物理化学
凝聚物质物理学凝聚物质物理学

背景情况:

玻璃和超冷液体中的离子运输是复杂的,经常显示非指数的衰变.
海文比率 (HR) 量化了因相关离子跳跃而导致随机行走扩散的偏差.
核磁共振旋格放松 (NMR SLR) 通过方向相关函数探测离子动态.

研究的目的:

为了研究海文比率 (HR) 与离子传输中的拉伸指数 (β) 之间的关系.
探索这种关系对理解超冷液体中的离子动态的影响.
确定β作为玻璃系统中HR的潜在代理.

主要方法:

对氧化物网络液体中离子的温度依赖的NMR SLR速率数据的分析.
从NMR SLR数据计算拉伸指数 (β).
计算的β值与现有的海文比率 (HR) 数据进行比较.

主要成果:

在各种超冷液体中,在HR和β之间发现了以前未知的近似相等性.
这种HR ≈ β关系支持静态网络中反向相关的离子跳跃模型.
从NMR SLR衍生的β可以在混合系统中估计特定物种的HR值.

结论:

拉伸指数 (β) 作为玻璃离子运输中的 Haven 比率 (HR) 的可靠代理.
这为在微观水平上探测离子扩散机制提供了一种新方法.
这些发现为超冷液体和玻璃中的离子动态提供了重要的见解.

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