A study of the applicability of many-body central force potentials in NiAl and TiAl
A study of the applicability of many-body central force potentials in NiAl and TiAl
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多体中心力势在NiAl和TiAl中的适用性研究
DOI：
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发表时间：
1999
期刊：
影响因子：
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通讯作者：
V. Vítek
中科院分区：
文献类型：
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作者：
V. Paidar;L. Wang;M. Šob;V. Vítek
通过研究NiAl和TiAl三种不同结构转化路径(四角形（B2L10）、三角形（B2L11）和六角形（B2B19）的能量变化，探讨了NiAl和TiAl的中心力多体势finni - sinclair型的适用性和特征。利用中心力势和全势线性化增广平面波（FLAPW）从头计算能量。这两种计算方法的比较为分析势能的效力提供了一种手段。中心力多体势非常满意地再现了NiAl的从头计算结果。这表明它们足以用于该化合物晶格缺陷的原子模拟。对于TiAl，中心力势在定性上模拟了从头计算的结果，但无法充分区分具有几乎相同的第一和第二相邻距离的结构。然而，目前的研究提供了一个理由，使用这些潜力时，调查扩展缺陷，其中第一和第二近邻的分离明显不同于那些在L10结构。
The applicability and characteristics of the central force many-body potentials of Finnis-Sinclair-type for NiAl and TiAl are investigated by studying the variation of the energy of these compounds with structural transformations that correspond to three distinct paths: tetragonal (B2L10), trigonal (B2L11) and hexagonal (B2B19). The energy was computed using both the central force potentials and the full potential linearized augmented plane waves (FLAPW) ab initio method. Comparison of these two calculations provides a means for the analysis of the efficacy of the potentials. The central force many-body potentials reproduce the results of ab initio calculations very satisfactorily for NiAl. This propounds that they are sufficient in atomistic modelling of lattice defects in this compound. For TiAl the central force potentials mimic the results of ab initio calculations qualitatively but are unable to differentiate adequately between structures with practically the same separations of the first and second neighbours. However, the present study provides a justification for the use of these potentials when investigating extended defects in which separations of the first and second nearest neighbours differ significantly from those in the L10 structure.