Dangling of electronic properties on different oxidation states in Mn-O system using LCAO, FP-LAPW and inelastic -ray scattering

Linear combination of atomic orbitals (LCAO) and full potential linearised augmented plane wave (FP-LAPW) approximations have been utilized to discuss the electronic properties for different form of binary manganese oxides viz. MnO, beta-MnO2, alpha-Mn2O3 and Mn3O4. Spin dependent energy bands and density of states (DOS) were computed using FP-LAPW-mBJ approximation. A significant band gap in both spin up and spin down channels for MnO, beta-MnO2 and Mn3O4 reflects their semiconducting nature, while alpha-Mn2O3 depicts the half metallic character. The Mulliken's charge reorganization on formation of oxides and Compton profiles (CPs) are also calculated using LCAO based pure and hybrid density functional theory. Mulliken analysis show that MnO, alpha-Mn2O3 and Mn3O4 have higher ionic character than that of natural beta-MnO2. Theoretical CPs for beta-MnO2 were validated by CP measurements using 100 mCi 241Am Compton spectrometer. It is shown that hybrid DFT (B3LYP) approximation is a better choice to evaluate electronic response, etc. Interdependence of energy bands (FPLAPW-mBJ) and anisotropic CPs are also discussed.