RuB_2结构与硬度的第一性原理研究(英文)

First-principles Study on Structure and Hardness of the RuB_2

采用第一性原理方法研究了RuB2六方结构和四方结构的晶体结构、弹性模量和电子结构。通过理论计算发现这两种结构的晶格参数和晶胞体积与实验值比较吻合,说明计算结果合理可信。计算的弹性模量显示这两种RuB2结构表现出优异的力学性能,通过电子结构的计算发现在Ru与B原子之间主要是以Ru的4d和B2p电子轨道上的电子杂化并形成了Ru-B共价键。在基态下RuB2主要以四方结构稳定存在。

The first-principles were employed investigate the structure properties, elastic constant and electronic structure of two phases of the RuB2 （orthorhombic and hexagonal phase）. The lattice parameter and volume of the two RuB2 phases are in good agreement with experimental values. The calculated elastic constants indicate that the RuB2 exhibits excellent mechanical properties. The electronic structure shows that hybridization occurs between Ru （d states） and B （p states） and form Ru-B covalent bonding forms. The results reveal that the hexagonal RuB2 is a stable phase at ground state.