Electronic structure and magnetic moment of dilute transition metal impurities in semi-metallic CaB6

• Published in: Journal of magnetism and magnetic materials Vol. 444; pp. 349 - 353
• Main Authors: Mohanta, S.K., Mishra, S.N.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15.12.2017; Elsevier BV
• Subjects: Density functional theory; Density of states; Dilution; Electronic structure; Electrons; Ferromagnetism; Impurities; Magnetic moments; Magnetic properties; Magnetism; Metals; Palladium; Platinum; Tantalum
• ISSN: 0304-8853; 1873-4766
• DOI: 10.1016/j.jmmm.2017.08.059

•A detailed and systematic study of electronic structure and local magnetism of 3d (Sc–Ni), 4d (Y–Pd) and 5d (La–Pt) impurities in semi-metallic CaB6 host has been presented.•The results show the existence of large magnetic moment for most of the impurities.•As an important feature we find high magnetic moment for 5d impurities like Ta, Re, Os, and Ir which are commonly regarded as being itinerant.•These results are expected to be useful for a comprehensive understanding of weak ferromagnetism observed in CaB6. Employing the all electron augmented plane wave+local orbital (APW+lo) method based on the density function theory (DFT), we have performed ab-initio calculations of electronic structure and magnetic properties of transition metal impurities doped in semi-metallic CaB6 host. Here, we present our results on the density of states (DOS), local magnetic moment and hyperfine field of 3d (Sc–Ni), 4d (Y–Pd) and 5d (La–Pt) in CaB6. Our results reveal strong localization of impurity d electrons yielding high local moments for most of the transition metal atoms, including the 5d atoms Ta, Re, Os and Ir. The results presented here would be useful towards a comprehensive understanding of the origin of weak ferromagnetism observed in CaB6. We believe that besides B or B6 vacancies which have been argued to be the main source of magnetism in CaB6, the local moments associated with different transition metal impurities can interact via conduction electron polarization and give rise to the weak ferromagnetism observed in this material.