Zn_3V_2O_8的电子结构与光学性质的理论研究

Theoretical Investigation on Electronic Structure and Optical Properties of Zn_3V_2O_8

采用平面波超软赝势密度泛函理论的方法研究了Zn_3V_2O_8的能带结构、电子态密度和光学特性。能带结果显示Zn_3V_2O_8呈间接带隙的绝缘体型能带,其禁带宽度为2.9 e V。详细的电子态密度结果显示其费米面上的态密度达到20 e/e V,费米能级附近的能级由Zn3p、V3p和O2p电子形成,Zn3d和O2s之间有强的杂化作用。介电性能结果显示在4.4~5.7 e V附近有强的吸收峰,在20.6 e V附近有一个次强吸收峰;吸收光谱显示在6.8 e V处有强吸收,在20.7 e V处有一个较弱的吸收峰。

The energy band structure,electron density of states and optical properties of Zn_3V_2O_8 have been studied by using the ultra-soft pseudo-potential density functional theory method. The band structure result reveals the indirect band gap of 2. 9 e V which exhibits its insulator characteristics. The electron density of states shows the high density of states at Fermi level of 20 e/e V,the bands near Fermi level are composed of Zn3p、V3p and O2p electrons,and high hybrids can be found between Zn3d and O2s electrons. The dielectric properties results show a high absorption peak at 4. 4-5. 7 e V and a weak absorption peak at 20. 6 e V; The optical absorption spectrum shows a strong absorption peak at 6. 8 e V and a weak absorption peak at 20. 7 e V.