Abstract
Generalized gradient approximation (GGA) computations based on the first-principles density functional theory (DFT) are executed to gain insight into the structural stability and physical properties of the 3d-transition-metalbased praseodymium series of perovskite compounds PrTO3. Correspondingly, to investigate the effect of on-site Coulomb repulsion energy, the exchange-correlation version of GGA is implemented via utilizing the (GGA+U) functional. The computed ground state energies (E-0) and equilibrium structural parameters of the varied T-site [T = Sc, Ti, V, Cr, Mn, Fe, Co] in the unit cell of PrTO3 reveal a cubic symmetry (Pm-3m) in all compounds, in a good match with the few existing DFT and experimental literature. Besides, the computed spin-polarized band structures and partial and total density of states (DOS) within GGA predict a half-metallic (HM) behaviour for [T = Sc] perovskite and a metallic nature for the rest [T = Ti, V, Cr, Mn, Fe, Co]. The analysis of E-0 results, DOSs and spin magnetic moments indicates that all perovskites PrTO3 are stable in a ferromagnetic (FM) phase via the double exchange interaction T3+-O2-T4+. PrTO3 show FM order with fractional values of their total spin magnetic moment per unit cell (M-PrTO3), except [T = Sc] perovskite that gives integer value (M-PrSeO3 approximate to 2.0 mu(B)) with HM-FM property. Conversely, it is found that PrTO3 exhibit HM-FM properties when [T = Sc, V, Cr, Mn, Fe] plus GGA+U is applied. Due to the cation-anion hybridizations, Pr3+-O2- and T3+ -O2-, both Pr3+ and T3+ ions contribute to the largest part of M-PrTO3 with minor effects coming from O2- ions and interstitials. Furthermore, the three-dimensional and two-dimensional electronic charge density plots of PrTO3 along the (110) plane confirm strong ionic nature along the Pr3+ -O2- bonds, whereas the other O2-T3+-O2- bonds have strong covalent character.