First-principles FLAPW calculations were performed on the Mn 2 CrZ (Z=Al, Ga, Si, Ge and Sb) alloys. Based on these results we predict two half-metallic ferromagnets (HMFs) namely Mn 2 CrAl and Mn 2 CrSb, and also find an energy gap in Mn 2 CrGa which lies near the Fermi level. The energy gap lies in the majority spin band for Mn 2 CrAl and Mn 2 CrGa, whereas in the minority one for Mn 2 CrSb. The calculated total spin magnetic moments M t cal are -1μ B per unit cell for Mn 2 CrAl and Mn 2 CrGa, +1μ B per unit cell for Mn 2 CrSb and zero for Mn 2 CrSi and Mn 2 CrGe, which agree with the Slater-Pauling rule. The calculation indicates a large and localized magnetic moment of Cr at B site. This is meaningful for searching for new half-metallic antiferromagnets in Heusler alloys. The magnetic moment of Cr is found to increase with increasing atomic number of Z and is antiparallel to that of Mn. The change of Mn and Cr spin moments compensates each other and keeps the total spin moment as an integer when the Z atom is changed.
- Band structure
- Heusler alloy
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics