Unveiling the metal–insulator-transition in NaIrO3: The role of spin-orbit coupling and strong electron correlation using ab initio method

Motivated by the unsuccessful attempts using the density functional theory (DFT) alone to study the insulating behavior of NaIrO${}_3$ post-perovskite compound, employing the interplay between the spin–orbit coupling (SOC) and strong electron correlation (U) effect, we have studied the structural, elastic, and electronic properties of this compound. Here, we have compared the effects of weak Jahn-Teller distortion, strong electron correlation at the transition metal and ligand sites, as well as the spin–orbit effect of the Ir atom to explore the insulating behavior of NaIrO${}_3$. This post-perovskite compound is associated with the tilting of octahedra in alternate layers, and the ab initio parameters are obtained to carry out this work. We employ the GGA+PBE approximation with full relativistic pseudopotentials to perform calculations including U and spin–orbit interactions within the Quantum Espresso package. From the elastic properties we have investigated that this compound is mechanically stable and ductile in nature. The compound also show anisotropic behavior at different planes.