极端不可压缩Re2P的电子结构、化学键及弹性性质的第一性原理研究

摘要

The electronic structures, chemical bonding and elastic properties of the Co2P-type structure phase ultra-incompressible Re2P (orthorhombic phase) were investigated by density-functional theory (DFT) within generalized gradient approximation (GGA). The calculated energy band structures show that the orthorhombic structure phase Re2P is metallic material. The density of state (DOS) and the partial density of state (PDOS) calculations show that the DOS near the Fermi level is mainly from the Re-5d state. Population analysis suggests that the chemical bonding in Re2P has predominantly covalent character with mixed covalent-ionic character. Basic physical properties, such as lattice constant, bulk modulus, shear modulus, and elastic constants Cij, were calculated. The elastic modulus and Poisson ratio were also predicted. The results show that the Co2P-type structure phase Re2P is mechanically stable and behaves in a brittle manner.%利用基于密度泛函理论(DFT)的广义梯度近似(GGA)，研究 Co2P 类型结构的极端不可压缩 Re2P 的电子结构、化学键和弹性性质。能带结构显示 Re2P 为金属性材料；态密度和分态密度的计算结果表明，费米能级附近的态密度主要来自Re-5d态；布居分析表明Re2P中的化学键具有以共价性为主的混合离子-共价特征。计算得到Re2P的晶格参数、体模量、剪切模量和单晶的弹性常数，由此导出弹性模量和泊松比。结果表明，Re2P是力学稳定的，且具有一定的脆性。