The Influence of Magnetism on Atomic Defects and Diffusion: Model Calculations and Ab Initio Electron Theory

摘要

The influence of magnetism on atomic defects and diffusion is investigated. First, already available model calculations are reviewed which describe the effect of an existing spin polarization on the diffusion coefficient. Then the effect of magnetism is investigated in a more fundamental sense by switching off and on the spin polarization in an ab-initio-electron-theory treatment. It turns out that the B2 structure of FeCo and the DO3 structure of Fe3Si become unstable with respect to the spontaneous formation of certain atomic defects by totally switching off magnetism. Magnetism is thus responsible for the observed phases and for the diffusion properties in these materials.