中文摘要：

采用基于密度泛函理论的第一性原理赝势平面波方法计算了Zr B2晶体的晶格常数、电子结构、弹性常数以及Debye温度。计算结果表明,采用广义梯度近似交换关联势与超软赝势得到的Zr B2晶格常数分别为a=0.316 81 nm和c=0.353 53 nm,与实验值相对误差仅为0.058%。B原子的2p轨道与Zr原子的4d轨道上的共价电子杂化是其产生“赝带隙”的主要原因。Mulliken布居分析表明,Zr原子有部分电子转移到B原子周围,产生了一定的离子键。为了研究应变幅对弹性常数计算结果的影响,采用了4种不同的应变幅,通过预设应力–应变法计算的Zr B2单晶的弹性模量矩阵,结果与实验值一致。通过弹性常数计算得到的Debye温度为927 K,也与实验值910 K吻合。

英文摘要：

The lattice constants, electronic structure, elastic constants, and the Debye temperature of ZrB2 crystal were calculated by first-principles total energy pseudo-potential methods based on density function theory. The results show that the balance lattice constants a and c of ZrB2 calculated by the general gradient approximation （GGA） exchange correlation function approximation method and ultrasoft pseudopotential scheme are 0.316 81 nm and 0.353 53 nm, with the relative errors of 0.058% and 0.058%, respectively, compared to the experimental data. The covalent electron hybridization between 2p orbitals of B atom and 4d orbitals of Zr atom is supposed as the main cause of＂pseudo-gap＂. The Mulliken population analysis indicates that a part of Zr electrons transfer to B atoms, leading to the ionic bonding in ZrB2 crystal. In order to investigate the effect of strain amplitude on the calculated results, four different strain amplitudes of the elastic constants were applied. According to the presetting strain and stress method, the theoretical values of elastic matrix for ZrB2 single crystal are similar to the experimental data. The Debye temperature of ZrB2 calculated based on elastic constants is 927 K, coincided with the experimental value （910 K）.