BaZr0.5Ti0.5O3电子结构、力学和光学性质的第一性原理研究

在广义梯度近似（GGA）下，采用基于密度泛函理论的第一性原理方法对BaZr0.5Ti0.5O3的电子结构、力学性质和光学性质进行了理论计算．计算得到该晶体的晶格常数为4.145925 Å，且此材料是一种间隙的半导体材料，价带和导带都来源于Ba原子、O原子的p态和Ti原子、Zr原子的d态电子间的杂化；力学性质的计算得到：BaZrO3和BaZr0.5Ti0.5O3的晶体结构稳定，且BaZrO3晶体掺杂Ti元素后体系的硬度变大；光学计算结果表明BaZr0.5Ti0.5O3的静态介电常数为4.20，吸收主要集中在低能区，静态折射率为2.00，能量损失峰出现在11.59eV处．上述研究结果为BaZr0.5Ti0.5O3材料的设计和应用提供了理论依据．

First-principles study of the electronic structures, mechanical and optical properties of BaZr0.5Ti0.5O3

The electronic structure, mechanical and optical properties of BaZr0.5Ti0.5O3 have been calculated by the first-principles method based on the density function theory with the generalized gradient approximation. The calculated results show that the crystal lattice constant of BaZr0.5Ti0.5O3 is 4.145925 Å and it is an indirect-band-gap semiconductor. Furthermore, its valance band and conduction band are derived from the hybridization among the p-states of Ba, O atoms and the d states of the Ti, Zr atoms. Calculations of the mechanical properties show that: the crystal structure of BaZrO3 and BaZr0.5Ti0.5O3 is stable, the hardness for the system of BaZrO3 crystal doped with Ti element becomes larger. The calculated optical properties show that the static dielectric constant is 4.20, and the absorption is mainly concentrated in the low energy region. The static refractive index is 2.00 and the energy loss peak is located at 11.59eV. The above results offer thoretical data for the design and application of the material BaZr0.5Ti0.5O3.