Abstract
The electronic band structures, density of states' plots and magnetic moments of Fe2MnSi, Fe2MnAl, and Co2MnGe are studied by using the first principles calculation. The FM solutions using LSDA without U show the presence of half-metallic ferromagnetic (HFM) ground state in Fe2MnSi, whereas the ground state of Fe2MnAl is found to be metallic. In both compounds the maximum contribution to the total magnetic moment is from the Mn atom, while the Fe atom contributes very less. The electronic structures and magnetic moments of Fe-based compounds are affected significantly by U under around-the-mean-field (AMF) double counting scheme, whereas its effect is very less on Co2MnGe. The magnetic moment of Fe atom in Fe2MnSi (Fe2MnAl) increased by ∼70% (∼75%) and in Mn atom it decreases by ∼50% (∼70%) when the value of U is increased from 1 to 5eV. Hund's like exchange interactions are increasing in Fe atom while decreasing in Mn atom with increase in U. The Fe and Mn moments are ferromagnetically coupled in Fe2MnSi for all values of U, whereas in Fe2MnAl they are coupled antiferromagnetically below U=2eV and ferromagnetically above it. Above U=2eV the metallic ground state of Fe2MnAl changes to semiconducting ground state and the ferromagnetic coupling between Fe and Mn atoms appears to be responsible for this. This shows that the validity of AFM double counting scheme is not robust for the entire range of U in the Fe2MnAl compound.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.