Band Calculation of Manganese Magnetic Moments in Ni₂MnGa 14M Structure

Abstract

For many years, many researchers had taken it for granted that the martensitic phase of Ni₂MnGa was the tetragonal structure. The common knowledge as regads the magnetic moment of the Heusler alloys including Mn was around 4.0 μ_B per formula unit (f.u.). However, Brown et al. newly observed the super-cell structure as the martensitic phase and reported the small magnetic moments on Mn in Ni₂MnGa. In this paper, the electronic structures are calculated and magnetic moments are estimated for Ni₂MnGa in the L2₁ and martensitic super-cell structures. In our calculation, we obtained a variety of magnetic moments on Mn in the martensitic structure and that values are largely different each other.