First-principles DFT computation of crystal, thermodynamic, magnetic and electronic structures of Sr-based perovskite-type oxides SrTO$_3$ (T = V, Cr, Mn, Co)

摘要

Examination of magnetic perovskite oxides ATO$_3$ containing 3 d -transition-metals has led to novel and functional compounds for many applications. Here, in this paper, we present detailed computations based on firstprinciples density functional theory (DFT) of the crystal, thermodynamic, magnetic and electronic structures of SrTO$_3$ (T = V, Cr, Mn, Co). Full potential linear muffin-tin orbital (FP-LMTO) method through the Perdew-Wang generalized gradient approximation (PW91-GGA) has been utilized in all computations. In addition, the effects of exchange-correlation energy (U) and spin-orbit (SO) coupling on magnetic and electronic structures have been investigated via(GGA+SO), (GGA+U) and (GGA+SO+U) methods. The computational results of crystal and thermodynamic structures revealed that all SrTO$_3$ stabilize in a cubic symmetry with ( a ${pprox}$3.80 A° ; space group Pm-3m). Besides, SrTO$_3$ compounds show ferromagnetic (FM) and metallic features, which transform to FM and half-metallic (HM) when U energy and SO coupling are included with GGA, except for (T = Co) that remains in its FM metallic nature. These parameters enhance the total density of states (DOS), partial DOSs and magnetic moments, and all obtained DFT results are in excellent agreement with the experimental data. Thus, the exciting HM–FM nature and stable crystal structures make SrTO$_3$ aseffective, promising and candidate material for modern spintronic applications.