Revisting Lennard Jones, Morse, and N-M potentials for metals
Revisting Lennard Jones, Morse, and N-M potentials for metals
复制标题
DOI：
10.1016/j.commatsci.2022.111206
复制
发表时间：
2022-02-02
影响因子：
3.3
通讯作者：
Thompson, Gregory B.
中科院分区：
文献类型：
--
作者：
Jacobson, David W.;Thompson, Gregory B.
Zhen和Davies在计算Lennard Jones N-M势参数时发现了一个重要的误差源。对这一误差进行了修正，并提出了一种新的更容易实现的确定N-M参数的方法。用这种新方法计算了38种金属元素的N-M参数以及莫尔斯和Lennard Jones的6-12参数。进行了分子动力学模拟，以说明新参数的准确性增加。使用Zhen和Davies参数预测的银的体积模量偏离约40%，而使用本研究中生成的参数计算的体积模量在实验值的2%以内。最后，讨论了每个潜在的类型描述不同的金属系统的局限性。特别地，对于参数“m”的小值，解决了N-M势随距离的过慢衰减速率。
A significant source of error was found in the paper by Zhen and Davies which is highly cited for use in calculating Lennard Jones N-M potential parameters. This error was corrected for and a new more easily implemented method for determining N-M parameters was developed. N-M parameters for 38 metallic elements were calculated using this new method in addition to Morse and Lennard Jones 6-12 parameters. Molecular dynamics simulations were carried out to illustrate the increased accuracy of the new parameters. The predicted bulk modulus of silver using Zhen and Davies parameters was off by approximately 40%, while the bulk modulus calculated using the parameters generated in this study was within 2% of the experimental value. Finally, a discussion on the limitations of each potential type for describing different metallic systems is presented. In particular, the overly slow decay rate of the N-M potential with distance is addressed for small values of parameter "m".