The Degree‐of‐Order Dependent Electronic Structures and Magnetic Properties of Fe 3 Si Alloys

• Published in: physica status solidi (b) Vol. 257; no. 5
• Main Authors: Xie, Jing, Liao, Yang-Fang, Wu, Dong-Ni, Xiao, Wen-Jun, Xie, Quan
• Format: Journal Article
• Language: English
• Published: 01.05.2020
• ISSN: 0370-1972; 1521-3951
• DOI: 10.1002/pssb.201900667

The effect of ordering degree on the electronic structures and magnetism of Fe 3 Si alloys are investigated scientifically using first‐principles calculations based on plane‐wave pseudopotential theory. The studied results of the heat of formation and cohesive energy for D0 3 and B 2 structures of Fe 3 Si reveal that the order of structural stability from high to low is B 2 ‐9, B 2 ‐8, B 2 ‐7, B 2 ‐6, D0 3 /B 2 ‐1, B 2 ‐2, B 2 ‐3, B 2 ‐4, and B 2 ‐5. Both D0 3 and B 2 structures of Fe 3 Si exhibit the metallic feature. A wider breadth of the pseudogap with occupation of Si sites by more Fe[B] atoms except B 2 ‐5 implies that the hybridization and covalent bond are intensified. Meanwhile, with substitution of Fe[B] atoms by more Si atoms, the stability of the system improves because the Fermi level is nearer to the bottom of the pseudogap. The origin of ferromagnetism for ordered Fe 3 Si except B 2 ‐9 is mainly from the Fe 3d spin polarization. Compared with D0 3 structure of Fe 3 Si, an increment in the concentration of Fe atoms with occupation of Si sites by more Fe[B] atoms causes the change of interaction between Fe and Si atoms and the total magnetic moment increases. On the contrary, the total magnetic moment decreases with gradual substitution of Fe[B] atoms by Si atoms.