Electronic structure and phase transition in polar ScFeO3 from first principles calculations

Abstract The properties of newly discovered polar ScFeO 3 with antiferromagnetic (AFM) ordering are examined using Ab initio calculations and symmetry mode analysis. The GGA +  U calculation confirms the stability of polar R 3 c phase in ScFeO 3 and the pressure induced phase transition to non-polar Pnma phase. Octahedron tilting and structural properties as a function of applied pressure have been analyzed. The origin of polar phase is associated with instability of non-polar R 3 ¯ c phase and group theory using the symmetry mode analysis has been applied to understand this instability as well as the spontaneous polarization of polar R 3 c phase. The magnetic phase transition shows G-type AFM ordering of Fe 3+ ion with energy scale of ∼200 meV/f.u., which can be understood by Goodenough-Kanamori theory. The magnetic easy axis calculation with spin orbit coupling confirms antiferromagnetic anisotropy in ScFeO 3 and spin canting may be realized within ∼0.2 meV/f.u.