Half-Metallic Ferromagnetic Predictions of Na2MgTiO6 Double Perovskite with Wide Band Gap


Özdemir E. G.

1st International Conference on Engineering and Applied Natural Sciences, Konya, Turkey, 10 - 13 May 2022, pp.1517

  • Publication Type: Conference Paper / Summary Text
  • City: Konya
  • Country: Turkey
  • Page Numbers: pp.1517
  • Gazi University Affiliated: Yes

Abstract

The half-metallic ferromagnetic properties of Na2MgTiO6 double perovskite compound were investigated with WIEN2k code [1-3]. The calculations were performed with PBE-GGA approximation [4,5]. First, the compound was formed in the 225-space group. Second, volume-energy optimization curve was performed, and FM phase was obtained energetically more stable than NM phase. The lattice parameter was obtained 7.89 Å. Then electronic properties were investigated, and the spin-up states of the compound showed semiconductor character. Here, the total band gap was obtained as 3.094 eV. The valence band maximum value is 2.664 eV while the conduction band minimum value is -0.430 eV. The half-metallic band gap of Na2MgTiO6 compound is -0.43015 eV. In spin-down states, the valence electrons showed metallic character as they were intertwined with the conduction band. Finally, the total magnetic moment of Na2MgTiO6 was obtained as 4.00 µB/f.u. When atomic comparisons were made, the most contribution to the magnetic moment came from O-atom. The high symmetry in the spin-up and spin-down densities of states of Na, Mg and Ti-atoms leads to bonded states of electrons in orbitals. These bounded states cause a decrease in spin contributions. However, the asymmetric electron distributions in the up and down spins of O-atom make the spin contributions more than the other atoms. This is directly reflected in the magnetic moment. Na2MgTiO6 double perovskite compound is a candidate material for use in spintronic applications with its electronic, magnetic, and high spin polarization.