Magnetism in Iron-Zirconium Systems

Abstract

The discrete variational method is used to solve the Khon-Sham equation in the spin-polarized local density approximation for Fe-Zr and Fe-Zr-H clusters, representing iron-zirconium and hydrogenated iron-zirconium alloys. The local magnetic moment and hyperfine field at the Fe site were found to decrease, whereas the contact charge density and occupation number were found to increase with Zr contents. The Zr site in clusters with high Fe contents acquires a negative magnetic moment. When H is trapped at an interstitial site next-neighboring an Fe atom, the magnetic moment and hyperfine field are enhanced, while the contact charge density is reduced. ‘The opposite occurs when H occupies a neighboring interstitial site to Fe. For Zr atoms the local magnetic moment is found to become less negative with H at the neighboring position. We conclude from this calculation that H is trapped in Fe-Zr systems at positions which are nearest to Zr and next-nearest to Fe atoms.