Investigation of Stable Structures and Electronic States of Spinel-Structured MgCo_2–<i>z</i>Ni_0.5MnAl_<i>z</i>O₄ (<i>Z</i> = 0, 0.3) as Cathode Materials for Magnesium Rechargeable Batteries Using First-Principles Calculations

The stable structures of pristine spinel MgCo2–zNi0.5MnAlzO4 (z = 0, 0.3) are elucidated by first-principles calculations. Electron-density and projected density states (PDOS) calculations performed for the z 0 0.3 compounds. calculated corresponding to well fitted pair distribution function (PDF) analysis with G(r) obtained synchrotron X-ray total scattering measurements. PDF reveals that agree experimental results. average electron between metal on 8a site oxygen in compound is lower than because reduced cation mixing Mg/Co compound, indicating weaker bonding. 16d higher stronger covalent Al–O bonding at more ionic Mg–O bonding, electrons bound Al localized, not shared surrounding atoms weaker. From our investigation, it could be predicted charge discharge capacities improved substitution atom instead part Co atom.