First principles investigation of the substitutional doping of Mn in Mg2Ni phase and the electronic structure of Mg3MnNi2 phase

▶ The substitutional doping of Mn in Mg2Ni phase and the electronic structure of Mg3MnNi2 phase have been investigated by first principles density functional theory calculations. ▶ The possibility of the site of Mn-substitution in Mg2Ni lattice has been confirmed to be Mg(6i) > Mg(6f) > Ni(3d) > Ni(3b) positions. ▶ The stability of phases gradually decreases along the sequence pure Mg2Ni phase > Mg3MnNi2 phase > Mn-substitution doped Mg2Ni phase, which is consistent with the experimental results. ▶ Analysis of density of states (DOS) indicates that the Mn substitution for Mg and Ni atom in Mg2Ni unit cell weakens the interaction between Mg s, Mg p and Ni d electrons. ▶ The cubic Mg3MnNi2 phase possesses a strong hybridization between Mn and Mg, Ni atomic orbits under simultaneously retaining the strong bonding between Mg s, Mg p and Ni d electrons.