Electronic structure and magnetism in compressed 3d transition metals

The authors present a systematic study of high-pressure effects on electronic structure and magnetism in 3d transition metals (Fe, Co, and Ni) based on x-ray magnetic circular dichroism measurements. The data show that the net magnetic moment in Fe vanishes above 18 GPa upon the transition to hcp Fe, while both cobalt and nickel remain ferromagnetic to well over 100 GPa. The authors estimate the total disappearance of moment in hcp Co at around 150 GPa and predict a nonmagnetic Ni phase above 250 GPa. The present data suggest that the suppression of ferromagnetism in Fe, Co, and Ni is due to pressure-induced broadening of the 3d valence bands. (c) 2007 American Institute of Physics.