Structural, optical, and thermal properties of MAX-phase Cr2AlB2  

作　　者：Xiao-Hong Li Hong-Ling Cui Rui-Zhou Zhang 

机构地区：[1]College of Physics and Engineering, Henan University of Science and Technology, Luoyang 471023, China [2]Department of Chemistry, Nanjing University of Science and Technology, Nanjing 210094, China [3]Henan Key Laboratory of Photoelectric Energy Storage Materials and Applications, Luoyang 471023, China

出　　处：《Frontiers of physics》2018年第2期93-101,共9页物理学前沿（英文版）

基　　金：This work was supported by the National Natural Science Foundation of China （Grant No. U1304111）, the Program for Science ＆ Technology Innovation Talents in Universi- ties of Henan Province （Grant No. 14HASTIT039）, and the Inno-vation Team of Henan University of Science and Technology （Grant No. 2015XTD001）.

摘　　要：First-principles calculations of the structural, optical, and thermal properties of Cr2AlB2 are performed using the pseudopotential plane-wave method within the generalized gradient approximation （GGA）. Calculation of the elastic constant and phonon dispersion indicates that Cr2AlB2 is mechanically and thermodynamically stable. Analysis of the band structure and density of states indicates that Cr2AlB2 is metallic. The thermal properties under increasing temperature and pressure are investigated using the quasi-harmonic Debye model. The results show that anharmonic effects on Cr^AlB~ are important at low temperature and high pressure. The calculated equilibrium primitive cell volume is 95.91 ~3 at T = 300 K, P - 0 GPa. The ability of Cr2AlB2 to resist volume changes becomes weaker with increasing temperature and stronger with increasing pressure. Analysis of optical properties of Cr2AlB2 shows that the static dielectric function of Cr2AlB2 is 53.1, and the refractive index no is 7.3. If the incident light has a frequency exceeding 16.09 eV, which is the plasma frequency of Cr2AlB2, Cr2AlB2 changes from metallic to dielectric material.First-principles calculations of the structural, optical, and thermal properties of Cr2AlB2 are performed using the pseudopotential plane-wave method within the generalized gradient approximation （GGA）. Calculation of the elastic constant and phonon dispersion indicates that Cr2AlB2 is mechanically and thermodynamically stable. Analysis of the band structure and density of states indicates that Cr2AlB2 is metallic. The thermal properties under increasing temperature and pressure are investigated using the quasi-harmonic Debye model. The results show that anharmonic effects on Cr^AlB~ are important at low temperature and high pressure. The calculated equilibrium primitive cell volume is 95.91 ~3 at T = 300 K, P - 0 GPa. The ability of Cr2AlB2 to resist volume changes becomes weaker with increasing temperature and stronger with increasing pressure. Analysis of optical properties of Cr2AlB2 shows that the static dielectric function of Cr2AlB2 is 53.1, and the refractive index no is 7.3. If the incident light has a frequency exceeding 16.09 eV, which is the plasma frequency of Cr2AlB2, Cr2AlB2 changes from metallic to dielectric material.

关 键 词：electronic structure optical properties first-principles calculations Cr2AlB2 THERMALPROPERTIES 

分 类 号：TS943.729[轻工技术与工程—服装设计与工程] TF526.1[冶金工程—钢铁冶金]