Abstract
Full-potential linearized augmented plane wave (FP-LAPW) method for an investigation of the structural, electrical, optical and magnetic properties of cubic manganese oxides in both spin channels was used. The calculated bond lengths and atomic positions for all the atoms are in good agreement with the recent experimental measurements. Electronic band structures calculations revealed that these materials have direct band gaps from the spin up case, while indirect band gaps from the spin down case, with the energy band gap of (Eg = 0.06 eV, Eg↓ = 4.23 eV), (Eg = 0.02 eV, Eg↓ = 4.28 eV) and (Eg = 0.04 eV, Eg↓ = 4.27 eV) for KMg4Mn6O15, RbMg4Mn6O15 and CsMg4Mn6O15, respectively. Overall, the behavior of these compounds is semiconductor have close concurrence with the experimental data. Spin up band gap is much lower in comparison to the spin down results. Density of states showed that valence and conduction bands are dominated by the Mn-d and O-p states. We also analyzed and discussed the optoelectronic properties in the energy range 0-10 eV to describe the absorption capability of these compounds. From the calculated magnetic moments, it is observed that all these compounds have high magnetic moments. The major contributions to the magnetic moment come from the Mn atoms.