First-principles calculations of pure elements: Equations of state and elastic stiffness constants
First-principles calculations of pure elements: Equations of state and elastic stiffness constants
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DOI：
10.1016/j.commatsci.2010.03.041
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发表时间：
2010-06
影响因子：
3.3
通讯作者：
S. Shang;A. Saengdeejing;Z. Mei;DongEung Kim;H. Zhang;S. Ganeshan;Yi Wang;Zi-kui Liu
中科院分区：
文献类型：
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作者：
S. Shang;A. Saengdeejing;Z. Mei;DongEung Kim;H. Zhang;S. Ganeshan;Yi Wang;Zi-kui Liu
采用广义梯度近似下的投影缀加波方法，对76种面心立方、体心立方和密排六方晶体结构的纯元素固体进行了系统的第一性原理计算，得到了能量-体积（E-V）状态方程和单晶弹性刚度常数（cij），其中cij由有效的应变-应力方法确定，EOS由4参数Birch-Murnaghan方程在第一原理E-V数据点上拟合。基于预测的状态方程和cij，分析了bcc，fcc和hcp结构之间的相变压力，结构稳定性和多晶聚集体的性质，包括体积模量（B），剪切模量（G），B/G比和各向异性比，并与实验数据进行了比较。目前对纯元素的系统研究不仅提供了状态方程和cij方程，而且提供了第一性原理计算的基准。
Using the projector-augmented wave method within the generalized gradient approximation, a systematic first-principles calculation for energy vs. volume (E–V) equations of state (EOS’s) and single crystal elastic stiffness constants (cij’s) has been performed for 76 pure elemental solids with face-centered-cubic (fcc), body-centered-cubic (bcc), and hexagonal-close-packed (hcp) crystal structures, wherein the cij’s are determined by an efficient strain–stress method, and the EOS’s are fitted by a 4-parameter Birch–Murnaghan equation upon the first-principles E–V data points. Based on the predicted EOS’s and cij’s, the phase transition pressures between bcc, fcc, and hcp structures, as well as the structural stabilities and the polycrystalline aggregate properties including bulk modulus (B), shear modulus (G), B/G ratio, and anisotropy ratio have been analyzed for pure elements and compared with available experimental data. The present systematic studies of pure elements provide not only the EOS’s and cij’s but also the benchmarks of first-principles calculations.