ELECTRONIC-STRUCTURES OF FEB, FE2B, AND FE3B COMPOUNDS STUDIED USING 1ST-PRINCIPLES SPIN-POLARIZED CALCULATIONS

The band structures of the ferromagnetic compounds FeB, Fe2B, and Fe3B were calculated using a spin-polarized version of the first-principles self-consistent orthogonalized linear-combination-of-atomic-orbitals method. Results on the band structure, density of states (DOS), and site-, orbital-, and spin-decomposed partial DOS are presented. Mulliken population analysis indicates B to be an electron accepter in these compounds due to the low-lying levels of the B 2s and B 2p states relative to the Fermi level. It is also shown that the moment on B is slightly polarized opposite to the Fe moments. The magnetic structure and bonding in these three compounds are further revealed by the presentation of contour maps for the charge density and the spin density. Our calculation shows an average spin magnetic moment of 1.26, 1.95, and 1.94B per Fe site and -0.10, -0.23, and -0.29B per B site in FeB, Fe2B, and Fe3B, respectively. The results are in reasonable agreement with photoemission and neutron-scattering measurements. The nature of the Fe-B bond is discussed in connection with the electronic structure of Nd2Fe14B intermetallic compounds and that of the Fe1-xBx metallic glasses. © 1990 The American Physical Society.