Atomistic simulation of oxide surfaces and their reactivity with water
Atomistic simulation of oxide surfaces and their reactivity with water
复制标题
氧化物表面及其与水的反应性的原子模拟
DOI：
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发表时间：
1999
期刊：
影响因子：
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通讯作者：
S. Redfern
中科院分区：
文献类型：
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作者：
S. C. Parker;N. H. Leeuw;S. Redfern
原子模拟是解释和预测表面结构的有价值的工具。本文介绍了我们目前的工作，旨在应用这种方法来模拟氧化物表面与水接触。所使用的原子模拟技术是能量最小化和分子动力学，这是再加上原子间的潜力。能量最小化使我们能够评估最稳定的表面构型，分子动力学提供了表面温度的影响。使用原子间势，它描述了原子之间的力，允许表面性质被快速计算，从而使我们能够增加所研究的系统的复杂性。我们已经扩展了我们以前的工作在两个方面，首先通过模拟水与更复杂的材料，如硅酸镁和氧化铁的相互作用，其次，通过考虑溶解的初始阶段，通过评估用质子取代表面阳离子的能量。我们发现表面和水之间有很强的相互作用。表面与水分子的键合由阳离子-水相互作用主导，但由每个水分子占据的面积（约为10 A2）调节。此外，正如预期的那样，溶解能高度依赖于阳离子配位和存在的阳离子的类型，Ca在能量上比Mg更有利，并且表面结构如Fe 2 O3所示。
Atomistic simulation is a valuable tool for interpreting and predicting surface structures. This paper describes our current work aimed at applying this approach to model oxide surfaces in contact with water. The atomistic simulation techniques used are energy minimisation and molecular dynamics, which are coupled with interatomic potentials. Energy minimisation allows us to evaluate the most stable surface configurations and molecular dynamics provides the effect of temperature on the surface. The use of interatomic potentials, which describe the forces between the atoms, allows the surface properties to be calculated rapidly hence enabling us to increase the complexity of the systems studied. We have extended our previous work in two ways, first by modelling the interaction of water with more complex materials such as magnesium silicate and iron oxide and secondly, by considering the initial stages of dissolution by evaluating the energies of replacing the surface cations with protons. We find that there is a strong interaction between the surfaces and water. The bonding of the surface to the water molecules is dominated by the cation–water interactions but is moderated by the area occupied by each water molecule, which is approximately 10 A2. In addition, as expected, the dissolution energies are highly dependent on cation coordination and the type of cation present, with Ca being energetically more favoured than Mg, and the surface structure as illustrated by Fe2O3.