Heterogeneous seeded molecular dynamics as a tool to probe the ice nucleating ability of crystalline surfaces.
Heterogeneous seeded molecular dynamics as a tool to probe the ice nucleating ability of crystalline surfaces.
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异质种子分子动力学作为探测晶体表面冰成核能力的工具。
DOI：
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发表时间：
2018
影响因子：
4.4
通讯作者：
A. Michaelides
中科院分区：
文献类型：
--
作者：
P. Pedevilla;Martin Fitzner;G. Sosso;A. Michaelides
冰成核在大量自然和技术过程中发挥着重要作用，但由于涉及的时间尺度（ns）和长度尺度（nm）短，因此通过实验研究具有挑战性。另一方面，传统的分子模拟难以应对临界冰核形成所需的相对较长的时间尺度。解决这个问题的一种方法是利用自由能或路径采样技术。不幸的是，这些计算成本很高。种子分子动力学是一种要求不那么高的替代方案，已成功应用于研究水的均匀冻结。然而，在异质冰成核的情况下，大自然最喜欢的形成冰的途径，必须在冰种子和感兴趣的基质之间建立一系列合适的界面，这不是一项简单的任务。在本文中，我们提出了一种异质种子化（HSEED）方法，该方法利用随机结构搜索框架来解决冰基底的挑战，从而能够对晶体表面上异质冰成核进行种子分子动力学模拟。我们通过研究冰在 (i) 模型晶体表面（使用粗粒 mW 模型）和 (ii) 胆固醇晶体（使用完全原子 TIP4P/冰水模型）上的成核来验证 HSEED 框架。我们表明，HSEED 技术产生的结果与元动力学和正向通量采样模拟都非常一致。由于其计算效率，HSEED 方法允许人们快速评估整个晶体基质库的冰成核能力，这是大气科学等领域期待已久的计算发展。
Ice nucleation plays a significant role in a large number of natural and technological processes, but it is challenging to investigate experimentally because of the small time scales (ns) and short length scales (nm) involved. On the other hand, conventional molecular simulations struggle to cope with the relatively long time scale required for critical ice nuclei to form. One way to tackle this issue is to take advantage of free energy or path sampling techniques. Unfortunately, these are computationally costly. Seeded molecular dynamics is a much less demanding alternative that has been successfully applied already to study the homogeneous freezing of water. However, in the case of heterogeneous ice nucleation, nature's favourite route to form ice, an array of suitable interfaces between the ice seeds and the substrate of interest has to be built, and this is no trivial task. In this paper, we present a Heterogeneous SEEDing (HSEED) approach which harnesses a random structure search framework to tackle the ice-substrate challenge, thus enabling seeded molecular dynamics simulations of heterogeneous ice nucleation on crystalline surfaces. We validate the HSEED framework by investigating the nucleation of ice on (i) model crystalline surfaces, using the coarse-grained mW model, and (ii) cholesterol crystals, employing the fully atomistic TIP4P/ice water model. We show that the HSEED technique yields results in excellent agreement with both metadynamics and forward flux sampling simulations. Because of its computational efficiency, the HSEED method allows one to rapidly assess the ice nucleation ability of whole libraries of crystalline substrates-a long-awaited computational development in, e.g., atmospheric science.
影响因子：
3.3
作者：
Cox, Stephen J.;Kathmann, Shawn M.;Michaelides, Angelos
通讯作者：
Michaelides, Angelos
影响因子：
15
作者：
Fitzner, Martin;Sosso, Gabriele C.;Michaelides, Angelos
通讯作者：
Michaelides, Angelos