First Principle Calculation of Electromagnetic Mechanism for Fe₂Si Bulk Material

Abstract

The electronic structure and the magnetic properties of Fe₂Si bulk have been calculated by the first-principle density function theory method. The band structure shows that the hexagonal Fe₂Si bulk is ferromagnetic which is a metal structure under spin-up, and a semiconductor with the band gap of 0.518 eV under spin-down. The density of states shows the Fe¹ 3d–spin and Fe³ 3d–spin in the electronic system are the main factors that is the source of the ferromagnetic properties of Fe₂Si bulk. The electronic structure Si-ions is 3s ² 3p ⁶ and that of Fe-ions is e _g ²↑e _g ^*1↓t _2g ³↑. The molecular magnetic moment of Fe₂Si is 2.00 μB. The potential diagram of Fe₂Si bulk shows the formation of covalent and ionic bonds between the Fe atom and the Si atom, it leads to the center charge of Fe is polarized and off center position. These special properties of Fe₂Si bulk are mainly caused by d-d exchange and p-d hybridization. The results offer a certain reference for the magnetic semiconductor Fe₂Si material.

Keywords

Fe₂Si / electronic structure / magnetic property / first-principle

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