Marzari, Nicola (Professor)Atlaw, Mesfin2018-07-122023-11-182018-07-122023-11-182009-06http://etd.aau.edu.et/handle/12345678/8383In this research work the electronic structure properties and lattice instability of BiMnO3 are examined by employing first principle DFT based techniques. First we perform a pseudopotential calculation using general gradient approximation without Hubbard U. The calculations are further extended adding U term to observe near effects to the Fermi. We also examine phonon dispersion for simple cubic ferromagnetic phase. Results for phonon show clear lattice instability to the off centered displacement driven by strong covalent bonding between Bi (6p) and O (2p) states. The entire work is carried out using Quantum-ESPRESSO. Some of our results are quite new and some matches with other recent findings.enBimno3Thesis