Evaluation of copper, aluminum, and nickel interatomic potentials on predicting the elastic properties
Evaluation of copper, aluminum, and nickel interatomic potentials on predicting the elastic properties
复制标题
DOI：
10.1063/1.4953676
复制
发表时间：
2016-06-28
影响因子：
3.2
通讯作者：
Zhang, Yuwen
中科院分区：
文献类型：
--
作者：
Rassoulinejad-Mousavi, Seyed Moein;Mao, Yijin;Zhang, Yuwen
选择适当的力场是任何原子模拟的主要关注点之一，需要认真考虑才能产生可靠的结果。由于对微/纳米尺度材料机械行为的研究变得越来越广泛，因此有必要确定足够的电势，以准确模拟所需应用的原子相互作用。在此框架中，研究了基于原子间势的多嵌入原子方法预测弹性性能的可靠性。在室温下对不同的铜、铝和镍原子间势进行了评估，这被认为是最适用的情况。检查的这三个物种的力场取自美国国家标准与技术研究院、桑迪亚国家实验室和 LAMMPS 数据库的在线存储库。利用分子动力学模拟，发现了 Cu、Al 和 Ni 立方单晶的三个独立弹性常数 C-11、C-12 和 C-44。然后采用 Voigt-Reuss-Hill 近似将单晶的弹性常数转换为各向同性多晶弹性模量，包括体积模量、剪切模量、杨氏模量以及泊松比。将大规模分子动力学的模拟结果与文献中可用的实验数据进行比较，以证明每个物种的每种潜力的稳健性。最终，建议使用准确的原子间势来寻找纯物质的每种弹性特性。发现弹性特性的精确度对力场的选择很敏感。适用于特定化合物的那些势可能不一定适用于所有现有的纯物质。本文中的表格结果可用作基准，以提高使用为问题指定的原子间势的保证。由 AIP 出版社出版。
Choice of appropriate force field is one of the main concerns of any atomistic simulation that needs to be seriously considered in order to yield reliable results. Since investigations on the mechanical behavior of materials at micro/nanoscale have been becoming much more widespread, it is necessary to determine an adequate potential which accurately models the interaction of the atoms for desired applications. In this framework, reliability of multiple embedded atom method based interatomic potentials for predicting the elastic properties was investigated. Assessments were carried out for different copper, aluminum, and nickel interatomic potentials at room temperature which is considered as the most applicable case. Examined force fields for the three species were taken from online repositories of National Institute of Standards and Technology, as well as the Sandia National Laboratories, the LAMMPS database. Using molecular dynamic simulations, the three independent elastic constants, C-11, C-12, and C-44, were found for Cu, Al, and Ni cubic single crystals. Voigt-Reuss-Hill approximation was then implemented to convert elastic constants of the single crystals into isotropic polycrystalline elastic moduli including bulk modulus, shear modulus, and Young's modulus as well as Poisson's ratio. Simulation results from massive molecular dynamic were compared with available experimental data in the literature to justify the robustness of each potential for each species. Eventually, accurate interatomic potentials have been recommended for finding each of the elastic properties of the pure species. Exactitude of the elastic properties was found to be sensitive to the choice of the force fields. Those potentials that were fitted for a specific compound may not necessarily work accurately for all the existing pure species. Tabulated results in this paper might be used as a benchmark to increase assurance of using the interatomic potential that was designated for a problem. Published by AIP Publishing.