First principles calculations of optical and magnetic properties of SrFe2O4 compound under pressure

• The magnetic properties in NM, FM, AFM and ferrimagnetic states under pressure.
• Ab initio approach was applied to calculate Hubbard parameter (U). The optical properties of SrFe2O4 were calculated under pressure.

In this research, the magnetic and optical properties of SrFe2O4 ceramic were studied. The calculations were performed by Full Potential Linearized Augmented Plane Wave method in Density Functional Theory framework with generalized gradient (GGA), GGA+U and modified Becke–Johnson approximations for the exchange and correlation functionals. The results show that SrFe2O4 is a ferrimagnetic ceramics with six different spin configurations. The Hubbard parameter was calculated (Ueff=4.5 eVUeff=4.5 eV) by an ab initio method. The optical properties such as dielectric function, refraction index, electron energy-loss function, reflectivity, absorption coefficient and optical conductivity were investigated at zero up to 20 GPa pressure in x, y and z directions. The pressure coefficients of optical band, static dielectric constant, plasmon peak, static refraction index and the maximum of absorption were determined. Moreover, the pressure dependence of the static dielectric constant, plasmon peak, static refraction index, the maximum of absorption and the optical gap were investigated.