Pressure effect on the electronic structure and optical properties of CaO based on first-principles calculations
LI Xiaoqin;XIAO Yatao;LU Yangong;SHEN Jie;ZHAO Hui;College of Physics and Materials Science,Tianjin Normal University;
To investigate the effect of changing pressure on electronic structure and optical properties of CaO crystal, the theoretical calculation and prediction of the crystal were carried out by using the first principles plane wave pseudo potential theory method based on density functional theory. The lattice constants obtained by the optimized method were basically consistent with the experimental values. The calculated results show that the crystal belongs to the indirect band gap insula-tor, the band gap value is 4.239 eV, the valence band top is mainly contributed by the O-p orbit, and the bottom of the conduction is contributed by the Ca-d rail. With the increase of the pressure, the real part of dielectric function and the peak value of refractive index decrease and red shift occurs, the peak value of imaginary part of dielectric function increase and the blue shift occurs, while the reflectivity, absorption coefficient and energy loss-function increase. Therefore, the change of the pressure can effectively change the electronic structure and optical properties of CaO.
【CateGory Index】： O76;O734