LOCAL SPIN-DENSITY THEORY OF MAGNETISM IN AMORPHOUS FE-B ALLOYS

Self-consistent spin-polarized calculations of the electronic and magn etic structure of amorphous FexB1-x alloys, based on realistic models of the glass-structure generated by a simulated molecular-dynamics que nch using tight-binding-bond forces between the atoms, are presented. The calculations predict average Fe moments in good agreement with exp eriment and small negative magnetic moments on the B sites whose origi ns are in a covalent coupling of the B p-states to the Fe spin-down ba nd. In the glass richest in Fe, a few Fe sites acquire a negative mome nt. It is found that the formation of negative Fe moments is due to a local-environment effect.