Study on the electronic structure and optical properties of the environmentally friendly semiconductor Ca3Si4

In this paper, electronic structure and optical properties of the bulk of the new-type environment friendly semiconductor material Ca3Si4 are investigated in detail by using first principles pseudo-potential calculations based on the density function theory. The calculation results show that: Ca3Si4 is a semiconducting material with an indirect band gap and the band gap is 0.375 eV; The valence bands of Ca3Si4 are mainly composed of Si 3p as well as 3s, the conduction bands are mainly composed of Ca 3d; The static dielectric constant is 20; The absorption coefficient maximum is 1.7×105 cm−1.