Ab initio DFT simulation of ideal shear deformation of SiC polytypes
Ab initio DFT simulation of ideal shear deformation of SiC polytypes
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DOI：
10.1088/0965-0393/15/2/003
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发表时间：
2007-03
影响因子：
1.8
通讯作者：
Y. Umeno;Y. Kinoshita;T. Kitamura
中科院分区：
文献类型：
--
作者：
Y. Umeno;Y. Kinoshita;T. Kitamura
我们进行从头算密度泛函计算，研究理想的SiC多型体（3C，2H，4H和6H）的剪切变形。立方和六方多型体在小应变区的变形可以很好地用组分Si_4C四面体的弹性性质来表示。多型体中的堆叠模式影响应变局部化，这与每个洗牌集平面的GSF能量分布和理想剪切强度相关。静水压应力降低了理想剪切强度，但对剪切弹性系数影响不大。Tersoff经典原子间相互作用势可以描述SiC晶体在小应变区的变形行为，但不能用于大剪切和压缩的情况。
We perform ab initio density functional calculations to investigate the ideal shear deformation of SiC polytypes (3C, 2H, 4H and 6H). The deformation of the cubic and hexagonal polytypes in the small-strain region can be well represented by the elastic property of component Si4C-tetrahedrons. The stacking pattern in the polytypes affects strain localization, which is correlated with the GSF energy profile of each shuffle-set plane and the ideal shear strength. Compressive hydrostatic stress decreases the ideal shear strength but does not much affect the shear elastic coefficient. Tersoff classical interatomic potential can represent the deformation behaviour of SiC crystals in the small-strain region but cannot be applied to largely sheared and compressed situations.