Mahadevan Thiruvilla S, Sun Wei, Du Jincheng
Department of Materials Science and Engineering , University of North Texas , Denton , Texas 76203 , United States.
J Phys Chem B. 2019 May 23;123(20):4452-4461. doi: 10.1021/acs.jpcb.9b02216. Epub 2019 May 9.
Molecular dynamics (MD) simulations provide important insights into atomistic phenomena and are complement to experimental methods of studying glass-water interaction and glass corrosion. For simulations of glass-water systems using MD, there is a need to for a reactive potential that is capable not only to describe the bulk and surface glass structures but also reactions between glass and water. An important aspect of the glass water interaction is the dissociation of water and its interaction with glass components that can result in the dissolution and alteration in the structure of glass. These phenomena can be efficiently simulated using "Reactive" potentials that allow for the dissociation of water while properly describing the bulk physical properties of water. We demonstrate a method to develop parameters for simulations of sodium silicate glasses and their interactions with bulk water. The developed parameter set was used to simulate sodium silicate glasses of different compositions, and the local structure of the simulated glass is in good compliance with experimentally obtained structural information. We also demonstrate that the parameter set predicts an accurate value for the hydration number and dissociation reactions of NaOH in water. Based on these results, we posit that these simple and computationally efficient reactive potentials can be used for further studies of water-induced structural modifications in sodium silicate glasses.
分子动力学（MD）模拟为原子现象提供了重要见解，是研究玻璃 - 水相互作用和玻璃腐蚀实验方法的补充。对于使用MD进行的玻璃 - 水系统模拟，需要一种反应势，它不仅能够描述玻璃的体相和表面结构，还能描述玻璃与水之间的反应。玻璃 - 水相互作用的一个重要方面是水的解离及其与玻璃成分的相互作用，这可能导致玻璃结构的溶解和改变。使用“反应性”势可以有效地模拟这些现象，这种势允许水的解离，同时正确描述水的体相物理性质。我们展示了一种为硅酸钠玻璃及其与大量水的相互作用模拟开发参数的方法。所开发的参数集用于模拟不同组成的硅酸钠玻璃，模拟玻璃的局部结构与实验获得的结构信息高度吻合。我们还证明，该参数集预测了水中NaOH的水合数和解离反应的准确值。基于这些结果，我们认为这些简单且计算高效的反应势可用于进一步研究水引起的硅酸钠玻璃结构改性。
