Magnetocrystalline anisotropy of α″–Fe16N2 under various DFT approaches

The magnetocrystalline anisotropy (MCA) energy of the giant saturation magnetization candidate material α″–Fe16N2 was investigated using first-principles electronic-structure calculations. The plane-wave density-functional theory (DFT) code Quantum ESPRESSO was employed to study the effect of different DFT approaches on the system, particularly the influence of exchange-correlation functionals and pseudopotential methods. The MCA energies obtained this way are within the range of previous theoretical and experimental results, while exhibiting significant variation between the different approaches. The role and limitations of these approaches in the view of Fe16N2 band structure are discussed in detail.