신소재 희토류 영구자석, Sm₂Fe17N₃ 화합물의 전자구조 연구

다국어 초록 (Multilingual Abstract)

Electronic and magnetic properties of the novel rare-earth permanent magnet, Sm₂Fe_(17)N₃, are investigated by performing self-consistent local density functional electronic structure calculations. Employing the LMTO (Linearized Muffin-Tin Orbital) band method, we have obtained the electronic band structures for both paramagnetic and ferromagnetic phases of Sm₂Fe_(17)N₃. Based on the energy band structures, we have studied bonding effects among Sm, Fe, and N atom as well as electronic and magnetic structures. It is found that the N atom substantially reduces the magnetic moment of neighboring Fe atoms through the hybridization interaction and also plays a role in stabilizing the structure. the average magnetic moment of Fe atoms in the ferromagnetic phase of Sm₂Fe_(17)N₃ is estimated to be 2.33μ_B, which is ~8 % larger than the magnetic moment of Sm₂Fe_(17), 2.16μ_B. The Fe Ⅰ (c) atom, which is located farthest from the N atom and surrounded by 12 Fe nearest neighbors, has the largest magnetic moment (2.65μ_B), while the Fe Ⅲ (f), whose hybridization interaction with N atom is very strong, has the smallest magnetic moment(1.96μ_B).