Computational Analysis of Structural, Electronic, Magnetic and Optical Properties of MgTM2O4 (TM = Fe, V) Spinels

The electronic behavior, ferromagnetism and optical characteristics of MgTM2O4 (TM = V, Fe) cubic spinels are investigated using the full-potential linearized augmented plane wave (FP-LAPW) approach, which involves concepts of density functional theory. The calculated band structures reveal half-metallic behavior in MgV2O4 and a ferromagnetic semiconducting nature in MgFe2O4. Moreover, the density of states (DOS) reveals that the magnetism results from the strong hybridization between Fe/V-3d and O-2p states, due to which Fe/V magnetic moments are reduced because magnetic moments appear at Mg and O sites. Hence, the spinels have importance for spintronic applications. The ferromagnetic phase stability is confirmed by the values of released energy, which are consistent with the computed values of the crystal field and exchange energies. The dielectric constant and refractive index values are large for MgV2O4 but small for MgFe2O4 due to their half-metallic and semiconducting nature, respectively. The blueshift of the absorption spectrum makes the spinels attractive for optical applications. The electrical and thermal conductivity are also computed using BoltzTraP code, and potential energy conversion applications are suggested.