  The effect of epitaxial strain on structural, magnetic and electronic
properties of BaFeO 3 per- ovskite oxide are investigated from first principles
calculations, using the Density Functional The- ory (DFT) plus the Hubbard
approach (DFT+U) within the Generalized Gradient Approximation (GGA). Hybrid
functional calculations, based on mixed exact Hartree-Fock (HF) and DFT
exchange energy functionals, are also performed. For the ground state
calculations,the DFT+U is found more suitable to describe the half metallic and
ferromagnetic state of cubic BaFeO 3 . The possible oc- curence of oxygen
octahedra rotations, Jahn-Teller distortions and charge orderings through
biaxial strain are explored. The obtained results reveal that the Jahn-teller
distortion is induced under tensile biaxial strain while the oxygen octahedra
rotations and breathing are unusualy not observed. Then, the strained BaFeO 3
is considered as a particular Jahn-Teller distorted perovskite with excep-
tional properties when compared to CaFeO 3 and SrFeO 3 . These findings lead to
a strain engineering of the JT distortions in BaFeO 3 , and thus for high
fundamental and technological interests.
