Mo2BC力学和电子性质的第一性原理研究

采用基于密度泛函理论(DFT)的第一性原理平面波超软贋势方法,对正交结构Mo2BC的力学和电子性质进行了系统的研究.计算结果表明,正交结构的Mo2BC在零压下是稳定的,优化得到的平衡结构参数与实验值符合得很好.Mo2BC的块体模量为308 GPa、剪切模量为187 GPa、弹性模量为471 GPa、泊松比为0.245,德拜温度是80 K.电子结构的分析表明,Mo2BC的化学键是共价键和离子键混合,表现出一定的金属性.

First-principles study of the mechanical and electronic properties of Mo2BC

In this paper,the mechanical and electronic properties of the orthorhombic Mo2BC are investigated by using the first-principle ultrasoft pseudopotential approach of the plane wave based on the density functional theory.The results show that the orthorhombic structure of Mo2BC are stable at zero pressure,and the optimized equilibrium lattice parameters are in good agreement with the experimental data.For the orthorhombic structure of Mo2BC,the obtained bulk,shear and elastic modulus are 308,187 and 471 GPa respectively.Poission’s ratio calculated is 0.245,and Debye temperature is 80 K.The bondings of Mo2BC are of the mixture of covalent and ionic bondings by the electron structures,and exhibit some metallic.