Abstract
Stable LaMnO3 (LMO) is successfully synthesized in cubic phase by hydrothermal process. The x-ray diffraction (XRD) results obtained are Rietveld refined which gives the best fit for cubic symmetry with space group Pm3m. Experimentally obtained lattice parameters were used to further investigate electronic, magnetic and elastic properties under extreme stress using Full-Potential Linearized Augmented Plane Wave (FP-LAPW) method within density functional theory (DFT). The experimentally observed lattice parameter is optimized by different exchange and correlation functional including LSDA, LSDA + U, GGA, and GGA + U. Also, the dynamic mean field theory (DMFT+DFT) is also employed to optimize the lattice parameter at room temperature which is in good agreement with experimental results. The electronic structure of the system depicts a half-metal to metal transition at 40 GPa. Elastic constants result shows that the cubic LMO is stable under hydrostatic pressure up to 50 GPa. This study provides important contribution in understanding the nature of cubic LMO which is a potential candidate for spintronic devices.