Size- and dimensionality-dependent thermodynamic properties of ice nanocrystals.
Size- and dimensionality-dependent thermodynamic properties of ice nanocrystals.
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DOI：
10.1021/jp211469e
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发表时间：
2012-02
期刊：
影响因子：
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通讯作者：
Y. Han;J. Shuai;H. M. Lu;X. Meng
中科院分区：
文献类型：
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作者：
Y. Han;J. Shuai;H. M. Lu;X. Meng
虽然冰的融化是最普遍的相变，（预）融化和准液体层仍然是一个有争议的问题，冰纳米晶体的热力学性质与它们的大小和维度之间的关系知之甚少。在这里，我们分析模型的大小和尺寸依赖的熔化温度，预熔温度，和熔化焓的氢键结合的冰纳米晶体。发现这三个热力学参数随尺寸和维数的增加而增加，其中尺寸效应是主要的，而维数效应是次要的，并且预熔温度的尺寸依赖性几乎遵循与熔化温度相同的趋势。模型预测对应于现有的分子动力学模拟和实验结果的冰纳米粒子和纳米线。这些协议使我们能够确定理论上的准液体层的厚度为第一次，这是发现是不恒定的，但略有增加，随着尺寸的增加，从而占不同的报告厚度的准液体层的发生。
Although the melting of ice is the most ubiquitous phase transition, (pre)melting and the quasi-liquid layer remain a matter of debate, and little is known about the relationship between the thermodynamic properties of ice nanocrystals and their size and dimensionality. Here, we model analytically the size- and dimensionality-dependent melting temperature, premelting temperature, and melting enthalpy of hydrogen-bonded ice nanocrystals. These three thermodynamic parameters are found to increase with increasing size and dimensionality where the size effect is principle while the dimensionality effect is secondary, and the size dependence of premelting temperature almost follows the same trend as that of melting temperature. The model predictions correspond to the available molecular dynamic simulation and experimental results of ice nanoparticles and nanowires. These agreements enable us to determine theoretically the thickness of the quasi-liquid layer for the first time, which is found to be not constant but slightly increase with increasing size and thus accounts for the occurrence of different reported thicknesses of the quasi-liquid layer.