ELECTRONIC-STRUCTURE AND FE MOMENT DISTRIBUTION IN A-FE1-XBX GLASS BY 1ST PRINCIPLES CALCULATIONS

The electronic structure and the magnetic properties of a-Fe80B20 glass have been studied by a first-principles approach. A large periodic model containing 160 Fe atoms and 40 B atoms is constructed by the Monte Carlo method. The spin polarized electronic structure of this glass model is calculated within the local density approximation using the orthogonalized linear combination of atomic orbitals method. The potential used is obtained from the self-consistent band structure calculation of ferromagnetic Fe3B. We find that the presence of B has not only reduced the average Fe moment per site, but has also significantly changed the shape of the distribution curve of the moment. The density of states for the spin-up and spin-down bands at the Fermi level in Fe80B20 are comparable, in sharp contrast to that of pure a-Fe. The B atoms are found to be slightly polarized in opposite direction to the moments of Fe as in the crystalline Fe-B compounds.