Structural, optoelectronic, infrared and Raman spectra of orthorhombic SrSnO3 from DFT calculations

Orthorhombic SrSnO3 was investigated using density functional theory (DFT) considering both the local density and generalized gradient approximations, LDA and GGA, respectively. The electronic band structure, density of states, complex dielectric function, optical absorption, and the infrared and Raman spectra were computed. Calculated lattice parameters are close to the experimental measurements, and an indirect band gap E(S→Γ)=1.97eV (2.27 eV) was obtained within the GGA (LDA) level of calculation. Effective masses for holes and electrons were estimated, being very anisotropic in comparison with similar results for orthorhombic CaSnO3. The complex dielectric function and the optical absorption of SrSnO3 were shown to be sensitive to the plane of polarization of the incident light. The infrared spectrum between 100 and 600 cm−1 was obtained, with its main peaks being assigned, and a nice agreement between experimental and theoretical peaks of the Raman spectrum of orthorhombic SrSnO3 was achieved.

Orthorhombic SrSnO3: a view of the unit cell (left) and plots showing the calculated and experimental Raman spectra (right).Figure optionsDownload as PowerPoint slideResearch highlights
► We have performed DFT calculations on orthorhombic SrSnO3 crystals, obtaining their structural, electronical and optical properties.
► An indirect band gap was obtained, and anisotropic effective masses were found for both electrons and holes.
► The complex dielectric function and the optical absorption of SrSnO3 were shown to be very sensitive to the plane of polarization of the incident light.
► The infrared spectrum between 100 and 600 cm−1 was obtained, with its main peaks being assigned, and a nice agreement between experimental and theoretical peaks of the Raman spectrum was achieved.