First-principles study of electronic structure and a large anomalous Hall effect in FeNi₃

In this work, we report the study of electronic structure, magnetism and a large anomalous Hall effect in a pristine bulk FeNi 3 , a member of Fe-Ni inver alloy materials, known as good metal catalysts with high activity and stability for water splitting for a very long time. Our prediction of large anomalous Hall effect in the bulk FeNi 3 may lead to the application for spintronics devices. While the previous literature [Shull and Wilkinson (1955 Phys. Rev. 97 304–310) mainly focused on the thermal and catalytic properties of FeNi 3, we report that the interplay of Fe d -Ni d hybridization and spin–orbit coupling give rise to large anomalous Hall effect and the ferromagnetic Weyl nodes in the bulk FeNi 3 . We predict a large intrinsic anomalous Hall conductivity of about 10000 S m −1 at the ground state. Furthermore, our study shows that the ground state of the bulk FeNi 3 is a Weyl metal with a large number of Weyl nodes at the Fermi energy away from high-symmetry k -points. In addition, we show the existence of Weyl nodes along the high symmetry k -points 0.2 eV above and 0.05 eV below self-consistent Fermi level. In this article, FeNi 3 has been studied to explore this scenario using first-principles density functional theory and subsequent Wannier90-based tight-binding method.