MAGNETIC FORM-FACTOR FOR ITINERANT-ELECTRON SYSTEMS

First-principles calculations of the itinerant-electron magnetic form factor for ferromagnets which include both the spin and orbital contributions have been completed for ferromagnetic nickel and iron. To our knowledge, these are the first calculations of this type for 3d ferromagnets. These calculations also include, by necessity, the spin-orbit interaction. Numerical results based on spin polarized bands used previously by Cooke et al. [Phys. Rev. B 21, 4118 (1980)] have been found to be in good agreement with experiment while results based on local density bands were found to be in good agreement for iron but not for nickel. In addition, it has been shown that if the energy dependence of the radial part of the wave functions can be ignored then the dominant terms in the itinerant-electron form factor can be written in a form almost identical to the atomic form factor. This provides an explanation for why fits to the atomic form factor have been so successful.