First principles on bcc and fcc phases structure of Fe₅₂T₂ (T=Cr,Mn,Co,Ni) alloys

Abstract

The lattice parameter, local magnetic moment and the relative stability of ferromagnetic bcc and antiferromagnetic fcc phases structure of Fe52T2(T=Cr,Mn,Co,Ni) alloys were studied by first principles method based on density functional theory. The results show that the dependence of lattice parameters and bulk modulus on the d shell electron number of dopant elements cannot be simply explained by the d band filling image. This fact suggests that there is a strong magneto-structural coupling effect in FeT alloys. For FeT alloys, the ferromagnetic bcc phase is more stable compared with the fcc phase. The antiferromagnetic phase is tetragonal with c/a ratio about 1.07, and this phase structure can be a metastable state. The change of lattice structure leads to redistribution of electrons, and thus results in different magnetic order and local magnetic moment.

Keywords

• Fe₅₂T₂ alloy
• bcc and fcc phase structure
• phase stability
• first principles calculation