Electronic structure, magnetic behavior, and stability of Ni-P

Electronic structure studies on Ni--P alloys have been carried out to elucidate the electronic and magnetic behavior and the stability of amorphous Ni--P glasses. The studies invoke a mixed approach where a cluster of atoms is treated accurately through ab initio techniques while the remaining solid manifests itself as an effective medium. The calculated electronic density of states show general features in agreement with specific-heat and photoemission experiments. The issue of disappearance of magnetism in Ni--P alloys with increasing phosphorus concentration is addressed. The studies show that this disappearance of magnetism is not accompanied by a filling of the transition-metal d band. On the contrary, the number of d holes remains nearly constant while the alloy demagnetizes itself through a modification of its electronic structure induced by P p states. The studies do not support any substantial charge transfers to or from P to Ni. The glass-forming ability of amorphous Ni--P glass within 15-26 at.% P is also discussed through realistic energy calculations. 28 ref.--AA