摘要
采用基于密度泛函理论(DFT)框架下广义梯度近似平面波超软赝势法,计算了板钛矿相TiO2的电子结构、态密度、电荷密度和光学性质。计算结果表明板钛矿相TiO2为直接带隙氧化物,禁带宽度为2.36 eV;计算并分析了板钛矿相TiO2的复介电常数、复折射率、光电导谱、吸收系数、反射率和损失函数,计算得到其静态介电常数为(100)、(010)和(001),方向分别为4.12、3.37和3.45,折射率分别为2.03、1.83和1.89;通过对比发现,由于板钛矿相TiO2晶体结构的对称性,在(100)、(010)和(001)方向上具有明显的光学各向异性,为板钛矿相TiO2的应用提供了理论参考数据。
Electronic structure,density of states,charge density and optical properties of brookite TiO2 have been investigated using the plane waves ultrasoft pseudopotential technique based on the density functional theory（DFT）.The calculated results show that brookite TiO2 is direct oxide with the band gap of 2.36eV.The complex dielectric function,complex of refractive index,complex conductivity function,absorption coefficients,reflectivity and loss function have been analyzed,and the results show that the static dielectric constants are 4.12,3.37 and 3.45,the refractivity index are 2.03,1.83 and 1.89 from（100）（010） and（001）.Because of symmetry struc-ture of crystal,brookite TiO2 shows a significant optical anisotropy in the polarization directions（100）,（010） and（001）,and the results offer a theoretical basis for the application of brookite TiO2.
出处
《北京联合大学学报》
CAS
2011年第1期78-82,92,共6页
Journal of Beijing Union University
