(中南大学 物理科学与技术学院，长沙 410083)
摘 要: 利用基于密度泛函第一性原理的GGA方法，研究ZnRh2O4的电子结构和光学性质。计算结果表明：ZnRh2O4具有明显的半导体能带结构特征，其带隙宽度为1.084 eV，且在费米能级附近的态主要由Rh的4d态构成。ZnRh2O4的静态介电常数为8.215，静态折射率为2.866，介电函数吸收边位于1.0 eV附近。在能量为0~8.44 eV区域，ZnRh2O4的反射系数随着能量的升高而逐渐增大；随后随能量的增大而逐渐减小；在能量为11.98 eV时，达到极小值，然后随能量的增大，再次逐渐增大；在能量为13.762 eV时，再次达极大值, 随后反射系数陡降；ZnRh2O4的吸收系数的数量级达105 cm−1，且吸收主要发生在低能区，其电子能量损失谱的共振峰在14.226 eV处，与此能量时反射系数的陡降相对应。
关键字: ZnRh2O4；电子结构；光学性质；第一性原理；介电常数；反射系数；吸收系数；能量损失
optical properties of ZnRh2O4
（School of Physical Science and Technology, Central South University, Changsha 410083, China）
Abstract:The first-principles calculations were carried out to investigate the electronic structure and optical properties of ZnRh2O4 using the method of the generalized gradient approximation (GGA) based on density functional theory. The results show that the band structure of ZnRh2O4 is a kind of semi-conducting material with wide-band gap of 1.084 eV. Near the Fermi level, Rh 4d is derived bands. The static dielectric constant of ZnRh2O4 is 8.215, and the static refractive index is 2.866. For the imaginary part of dielectric constant, the absorption starts at about 1.0 eV. When the energy is 0−8.44 eV, the reflection index increases with increasing energy, and decreases to the minimum till 11.98 eV, and then increases with the increase of the energy again till 13.762 eV. There is an abrupt reduction when the energy is a little higher than 13.762 eV, which corresponds to the peak of electron energy loss spectrum (EELS). The absorption coefficient is as large as 105 cm−1, and the absorption mainly locates in the low energy region.
Key words: ZnRh2O4; electronic structure; optical properties; first-principles; dielectric function; refractive index; absorption coefficient; energy loss
