CdGeAs2晶体的结构、弹性和电子性能的模拟计算和分析(英文)

Simulative Calculation and Analysis of Structural,Elastic and Electronic Properties of CdGeAs_2

利用基于密度泛函理论的平面波赝势法对CdGeAs2晶体的结构,弹性和电子性能进行了研究。CdGeAs2晶体具有6个独立的弹性常数,利用计算的弹性性能可以判断晶体具有机械稳定性、延性和弹性各向异性等力学特点。通过总的和部分态密度分析了不同能带的贡献成分。计算的结构参数及弹性常数与实验值基本吻合。CdGeAs2晶体具有直接能隙,禁带宽为0.05 eV,并且具有共价特性。此外,通过电子等密度线以及Mulliken键布局表明,Cd–As键的共价性要强于Ge–As键的。

The structural,elastic and electronic properties of CdGeAs2 have been investigated using the plane wave pseudopotential method based on density functional theory.The structure of CdGeAs2 can be characterized by six independent elastic constants,and the mechanical stability,ductility and strong elastic anisotropy of CdGeAs2 were confirmed by the calculated elastic properties.The contribution of the different bands was analyzed from total and partial densities of states.The calculated structural parameters and elastic constants are in good agreement with the experimental values.CdGeAs2 has a direct band gap of 0.05 eV and it has some co-valent features.Furthermore,from the electron density contour as well as Mulliken bond populations,it is found that the Cd–As bond possesses stronger covalence than the Ge–As bond.