Magnetic and structural properties of Fe/sub 3/GeN/sub x/

Magnetic and structural properties of Fe/sub 3/GeN/sub x/ have been investigated. The FCC (face centered cubic) phase of FeGe absorbs nitrogen to x=0.24. As a result of absorption, the Curie temperature and room temperature magnetization decrease from 736 K and 137 emu/g to 614 K and 74 emu/g, respectively. The HCP (hexagonal close packed) phase of Fe/sub 3/Ge, however, transforms to either FCC tetragonal phase, or a combination of these upon nitrogenation. The tetragonal nitride phase forms at a reaction temperature of 600 degrees C to 650 degrees C in a flowing atmosphere of ammonia. The phase is paramagnetic at room temperature and appears to order antiferromagnetically below 100 K.<
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