Atomic‐Scale Modelling of Electrochemical Systems
Atomic‐Scale Modelling of Electrochemical Systems
复制标题
电化学系统的原子尺度建模
DOI：
10.1002/9781119605652
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发表时间：
2021
影响因子：
32.5
通讯作者：
K. Laasonen
中科院分区：
文献类型：
--
作者：
Marko M. Melander;T. Laurila;K. Laasonen
本章介绍并描述了一种新的第一性原理计算电化学方法，它在现有方法中占据了独特的中间位置，提供了替代方法的优点而没有随之而来的缺点。当然，第一原理方法是发展真正具有预测性和准确性的计算电化学的正确途径，但需要非常小心地避免还原论的陷阱。例如，电子和核坐标的完整多体波函数的知识，即使以某种方式获得，也会过于详细，无法提供有用或信息。此外，这样的描述本身并不是真正的“第一性原理”，因为它不会考虑原子核内部的过程，而且很可能会忽略各种相对论性过程。与任何科学追求一样，人们必须根据适当选择的实体来描述自然。如果最终的描述是定量预测的，那么所选择的实体遵循的定律也必须是定量预测的。本工作的前一章（第3章）提出了一种方法，该方法从电子和原子核以及量子力学定律的角度来处理电化学系统的活性组分，但将电解质视为一种有效的连续介质，它对系统的活性组分作出反应并起作用（图4.1 (c)）。这种方法通过认识到电解液中绝大多数原子的位置和排列的精确细节在很大程度上与电化学过程无关，从而获得了巨大的计算效益。通过从根本上降低计算成本，这种方法具有科学上的好处，可以研究更复杂的系统，探索比通过跟踪组成电解质的原子位置所能研究的多得多的不同系统。然而，连续体方法确实牺牲了一些准确性和预测能力，因为活性电化学过程附近电解质原子的明确排列（“壳结构”）可能非常重要，也可能对电化学本身有直接的兴趣。作为连续体方法的补充，接下来的两章（第5章和第6章）提出了分子动力学方法，直接与所有电解质原子的详细排列的完整统计数据相竞争（图4.1 (a)）。后一种方法处理
This chapter introduces and describes a novel approach to first principles computational electrochemistry that occupies a unique intermediate niche among available approaches, offering the advantages of the alternate approaches without the consequent disadvantages. While, certainly, a first principles approach is the right path for the development of a truly predictive and accurate computational electrochemistry, great care is needed to avoid the pitfalls of reductionism. For example, knowledge of the full many-body wave function of electronic and nuclear coordinates, even if somehow obtainable, would be far too detailed to be useful or informative. Moreover, such a description itself would not be truly ‘first principles’, as it would not consider processes within the nuclei and likely would ignore various relativistic processes. As with any scientific pursuit, one must describe nature in terms of appropriately chosen entities. If the resulting description is to be quantitatively predictive, so too must be the laws which the chosen entities follow. The preceding chapter of this work (Chapter 3) presents an approach which treats the reactive components of an electrochemical system in terms of electrons and nuclei and the laws of quantum mechanics, but which treats the electrolyte as an effective continuum material that responds to and acts upon the active components of the system (Figure 4.1 (c)). This approach gains a great computational benefit by recognizing that the precise details of the locations and arrangements of the vast majority of the atoms in the electrolyte are largely irrelevant to electrochemical processes. By radically reducing computational costs, this approach has the scientific benefit of allowing for the study of much more complex systems and the exploration of far more varied systems than could be studied through an approach tracking the positions of the atoms making up the electrolyte. The continuum approach, however, does sacrifice some accuracy and predictive power because the explicit arrangements of electrolyte atoms (‘shell structure’) near an active electrochemical process can be quite important and also may be of direct interest in themselves to electrochemistry. Complementing the continuum approach, the two following chapters (Chapters 5 & 6) present molecular dynamics approaches contending directly with the full statistics of the detailed arrangements of all of the electrolyte atoms (Figure 4.1 (a)). This latter approach deals