All-electron study of ultra-incompressible superhard material ReB_2: structural and electronic properties  

作　　者：李延龄 钟国华 曾雉 

机构地区：[1]Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences [2]Graduate School of the Chinese Academy of Sciences [3]Department of Physics, Xuzhou Normal University

出　　处：《Chinese Physics B》2009年第10期4437-4442,共6页中国物理B（英文版）

基　　金：Project supported by the Special Funds for Major State Basic Research Project of China (Grant No 2007CB925004);863 Project;Knowledge Innovation Program of the Chinese Academy of Sciences;Director Grants of CASHIPS

摘　　要：This paper investigates the structural and electronic properties of rhenium diboride by first-principles calculation based on density functional theory. The obtained results show that the calculated equilibrium structural parameters of ReB2 are in excellent agreement with experimental values. The calculated bulk modulus is 361 GPa in comparison with that of the experiment. The compressibility of ReB2 is lower than that of well-known OsB2. The anisotropy of the bulk modulus is confirmed by c/a ratio as a function of pressure curve and the bulk modulus along different axes along with the electron density distribution. The high bulk modulus is attributed to the strong covalent bond between Re-d and B-p orbitals and the wider pseudogap near the Fermi level, which could be deduced from both electron charge density distribution and density of states. The band structure and density of states of ReB2 exhibit that this material presents metallic behavior. The good metallicity and ultra-incompressibility of ReB2 might suggest its potential application as pressure-proof conductors.This paper investigates the structural and electronic properties of rhenium diboride by first-principles calculation based on density functional theory. The obtained results show that the calculated equilibrium structural parameters of ReB2 are in excellent agreement with experimental values. The calculated bulk modulus is 361 GPa in comparison with that of the experiment. The compressibility of ReB2 is lower than that of well-known OsB2. The anisotropy of the bulk modulus is confirmed by c/a ratio as a function of pressure curve and the bulk modulus along different axes along with the electron density distribution. The high bulk modulus is attributed to the strong covalent bond between Re-d and B-p orbitals and the wider pseudogap near the Fermi level, which could be deduced from both electron charge density distribution and density of states. The band structure and density of states of ReB2 exhibit that this material presents metallic behavior. The good metallicity and ultra-incompressibility of ReB2 might suggest its potential application as pressure-proof conductors.

关 键 词：FIRST-PRINCIPLES INCOMPRESSIBILITY electronic property 

分 类 号：TB303[一般工业技术—材料科学与工程]