Structural, electronic and optical properties of orthorhombic image from first principles calculations

Orthorhombic perovskite CdGeO3CdGeO3 was studied using the density-functional theory (DFT) formalism. The electronic band structure, density of states, effective masses, dielectric function and optical absorption were obtained. Comparing with orthorhombic CaGeO3CaGeO3, which is an indirect S→ΓS→Γ gap material, the substitution of calcium by cadmium changes the valence band maximum from the S point to the ΓΓ point in reciprocal space, and decreases the Kohn–Sham band gap energy. Our results suggest that orthorhombic CdGeO3CdGeO3 has features of a semiconductor and is potentially useful for optoelectronic applications.