使用基于密度泛函理论的第一性原理赝势平面波方法,对Ca3Si4块体进行了详细的计算研究,得到了金属间化合物Ca3Si4是一种间接带隙半导体,禁带宽度为0.372 eV;价带主要由Si的3s和3p态电子构成,导带主要由Ca的3d态电子构成。其光学性质结果为:静态介电常数为19,折射率为4.35,吸收系数最大峰值为1.56×105cm-1,能量损失峰的最大值约在8.549 eV处。 Calculating the Ca3Si4 bulk with a first-principle pseudopotential plane wave method based on the density functional theory, the intermetallic compound Ca3Si4 is an indirect bandgap semiconductor with a forbidden band width of 0.372 eV. The valence band It is mainly composed of 3s and 3p states of Si, and the conduction band is mainly composed of 3d electrons of Ca. Its optical properties are as follows: the static dielectric constant is 19, the refractive index is 4.35, the maximum absorption peak is 1.56 × 105cm-1, and the maximum energy loss peak is about 8.549 eV.