Antiferromagnetism of Fe_1+δSb

Abstract

Fe 1+δ Sb (0.08≤δ≤0.38) crystallizes in the NiAs structure, and the excess Fe atoms occupy the interstitial positions. The Mössbauer effect measurements show that at liquid nitrogen temperature and below, an antiferromagnetic order sets in, and the internal magnetic field at liquid helium temperature amounts to 106 kOe. The Néel temperature, however, is not discernible in the susceptibility measurements. The susceptibility shows a maximum at around 20 K, whose origin is supposed to be due to spin ordering of excess Fe atoms.