Development of Finnis-Sinclair potential of metal Nb and the influence of potential function form on the properties of material

doi:10.7498/aps.70.20202168

IMR OpenIR

	Development of Finnis-Sinclair potential of metal Nb and the influence of potential function form on the properties of material
	Gao Jing-Yi 1; Sun Jia-Xing 1; Wang Xun 2; Zhou Gang 3; Wang Hao 3; Liu Yan-Xia 1; Xu Dong-Sheng 3
通讯作者	Liu Yan-Xia(ldlyx@163.com)
	2021-06-05
发表期刊	ACTA PHYSICA SINICA
ISSN	1000-3290
卷号	70 期号:11 页码:14
摘要	Researchers' work on computational materials is often hampered by the lack of suitable intera tomic potentials. In this paper, under the framework of Finnis-Sinclair (FS) potentials, the process of fitting, testing and correction of interatomic potential is given in detail by developing the FS potential for metal Nb. First, the relationship between the interatomic potential and the macroscopic properties of the material is established. Then, the Finnis-Sinclair potential of metal Nb is fitted by reproducing the experimental data, such as the cohesive energy, bulk modulus, surface energy, vacancy formation energy and equilibrium lattice constant, and the fitting mean square error is less than 10(-7). In order to test the interatomic potential, the elastic constant, shear modulus and Cauchy pressure of metal Nb are calculated by the constructed interatomic potential. In addition, how the form of the interatomic potential function affects the interstitial performance is discussed, and the constructed interatomic potential is modified according to the results of density functional theory (DFT) of the interstitial formation energy. The treatment of cutoff distance is also discussed. In the paper, the results are as follows. 1) The original form of FS potential is not suitable for extending the atomic interaction to the third nearest neighbor. Through analysis and test, it is found that when the modified electron density function is in the form of the fourth power and the form of the pair potential function is in the form of the sixth power polynomial, the interatomic potential can better describe the interatomic interaction; 2) The result of interstitial formation energy is taken as the target value to modify the behavior of the pair potential function in the near distance, and the modified interatomic potential gives the interstitial formation energy close to the result of DFT. When the interstitial energy calculated by the interatomic potential is larger than the target value, the pair potential curve of near distance will be softened by the superposition of a polynomial term, otherwise, the pair potential curve will be stiffened; 3) When the physical quantity under equilibrium state is used as the fitting data, the fitted potential parameters and the elastic constant results will not be affected, while adjusting the curve form of the potential function, as long as none of the function value, the slope and the curvature of the function curve is changed at each neighbor position. The magnitude of interstitial energy will be affected by changing the shape of the curve that is less than the first neighbor range; 4) Under the cutoff strategy in this paper, changing the cutoff distance has almost no influence on the calculated results of potential parameters or crystal properties, but has a slight influence on the mean square error of the fitting results. The results of this paper provide some information for the construction of interatomic potentials database, and lay a foundation for constructing the Nb-related interatomic potential of alloy. And it also provides a method and basis for developing and improving the quality of interatomic potential.
关键词	construction of interatomic potential metal Nb Finnis-Sinclair potential function form of interatomic potential
资助者	National Key Research & Development Program of China
DOI	10.7498/aps.70.20202168
收录类别	SCI
语种	英语
资助项目	National Key Research & Development Program of China[2016YFB0701304]
WOS研究方向	Physics
WOS类目	Physics, Multidisciplinary
WOS记录号	WOS:000659877700008
出版者	CHINESE PHYSICAL SOC
引用统计
文献类型	期刊论文
条目标识符	http://ir.imr.ac.cn/handle/321006/159939
专题	中国科学院金属研究所
通讯作者	Liu Yan-Xia
作者单位	1.Liaoning Univ, Coll Phys, Shenyang 110036, Peoples R China 2.Shenyang Jianzhu Univ, Sch Sci, Shenyang 110168, Peoples R China 3.Chinese Acad Sci, Inst Met Res, Shenyang 110016, Peoples R China
推荐引用方式 GB/T 7714	Gao Jing-Yi,Sun Jia-Xing,Wang Xun,et al. Development of Finnis-Sinclair potential of metal Nb and the influence of potential function form on the properties of material[J]. ACTA PHYSICA SINICA,2021,70(11):14.
APA	Gao Jing-Yi.,Sun Jia-Xing.,Wang Xun.,Zhou Gang.,Wang Hao.,...&Xu Dong-Sheng.(2021).Development of Finnis-Sinclair potential of metal Nb and the influence of potential function form on the properties of material.ACTA PHYSICA SINICA,70(11),14.
MLA	Gao Jing-Yi,et al."Development of Finnis-Sinclair potential of metal Nb and the influence of potential function form on the properties of material".ACTA PHYSICA SINICA 70.11(2021):14.