中文摘要：

根据密度泛函理论,采用模拟计算软件CASTEP计算了含有氧空位钛酸钡晶体的电子结构和光学性质。结果表明,氧空位的存在没有在禁带中引入缺陷能级,但氧空位的存在对晶体的光学性质产生显著的影响。并得到氧空位的存在将引起钛酸钡晶体出现440～450 nm吸收峰的结论。

英文摘要：

The electronic structures and optical properties of the perfect BaTiO3 crystal and the crystal containing VOhave been calculated using CASTEP codes. The calculated results indicate that the oxygen vacancy in the form of isolated single vacancy in BaTiO3 crystal does not create the localized state in the band gap,which consistent with many experimental studies. However,the oxygen vacancy existing in the crystal will obviously affect optical properties of the BaTiO3. The occurrence of the 440-450 nm absorption band is related with the oxygen vacancy.